Newbie best notes - Codeforces

#	User	Rating
1	tourist	4009
2	jiangly	3823
3	Benq	3738
4	Radewoosh	3633
5	jqdai0815	3620
6	orzdevinwang	3529
7	ecnerwala	3446
8	Um_nik	3396
9	ksun48	3390
10	gamegame	3386

#	User	Contrib.
1	cry	167
2	maomao90	163
2	Um_nik	163
4	atcoder_official	161
5	adamant	159
6	-is-this-fft-	158
7	awoo	157
8	TheScrasse	154
9	nor	153
9	Dominater069	153

Language using with: C

Datatype resource
BASIC OF VARIABLE & CONSTANT resource
OPERATOR resource
TYPECASTING resource
LIBRARY-FUNCTION resource
RELATIONAL AND- LOGICAL OPERATORS resource
IF-ELSE STATEMENT resource
TYPE-CASTING resource
POST & PRE-INCREMENT resource
TERNARY-OPERATOR resource
PATTERN PRINTING resource Youtube
BASIC DATATYPES{*char} class
SWITCH-CONTINUE- GOTO-DO.WHILE class
ARRAY class:1D class:2D Youtube
STRING Youtube class:2D
FUNCTION resource
RECURSSION class:1 class:2

Try to solve this problem using with Loop:

219432Y-Easy Fibonacci

Code

#include<stdio.h>    
int main()  
{    
   int a=0, b=1, c, i, n;       
   scanf("%d", &n);         
   if(n == 1)        
       printf("%d", a);         
   else      
       printf("%d %d", a, b);     
     
   for(i=1; i<=n-2; i++)         
   {      
      c = a + b;      
      printf(" %d", c);            
      a = b;            
      b = c;               
   }          
     printf("\n");             
     return 0;           
  }

219432J-Primes from 1 to n

Code

#include<stdio.h>
int main()          
{          
   int i, n, x, f, j;      
   scanf("%d", &n);       
   i = 1;     
   while(i <= n)           
   {           
      f = 0;           
      x = i;           
      for(j=2; j<x; j++)
      {      
          if(x%j == 0)       
          {           
              f++;           
          }        
      }        
       if(f == 0 && x != 1)       
       {     
           printf("%d ", x);         
       }          
      i++;      
   }        
  return 0;         
}

219432G-Factorial

Code

#include<stdio.h>                 
int main()    
{          
   long long int n, i, j, x, fact;                
   scanf("%lld", &n);              
   i=1;                      
   while(i<=n)        
   {                             
      scanf("%lld", &x);                 
      fact = 1;              
      for(j=1; j<=x; j++)                                 
      {                         
          fact *= j;                                    
      }                   
      printf("%lld\n", fact);      
      i++;                     
   }                                  
    return 0;                              
}

219432I-Palindrome

Code

#include<stdio.h>
int main()
{
   int n, r, s=0, x;
   scanf("%d", &n);
    x = n;
    while(x>0)
    {
      r = x % 10;
      s = s*10+r;  
      x /= 10;     
    }
    if(n == s)
    {
        printf("%d\n", s);
        printf("YES");
    }
     else
     {
        printf("%d\n", s);
        printf("NO");
     }
  return 0;
}

219432L-GCD

Code

#include<stdio.h>
int main()
{
   int i, n, x, a, b, c=0;
   scanf("%d%d", &a, &b);
   i=1;
   while(i<=a && i<=b)
   {
       if(a%i==0 && b%i==0)
        {
            c = i;
        }
       i++;
   }
    printf("%d", c);
    return 0;
}

---------------------------------------------------------------

Try to solve this proble using with Array:

219774D-Positions in array

Code

#include<stdio.h>
int main()
{
     int n, i, x, r, f, m, j, pos;
     int arr[100010];
     scanf("%d", &n);
     for(i=0; i<=n-1; i++)
     {
         scanf("%d", &arr[i]);
     }
     pos=0;  
     for(i=0; i<=n-1; i++)
     {  
           while(arr[i] <= 10)
           {
             pos=arr[i];
             printf("A[%d] = %d\n", i, arr[i]);
             break;
           }
     }
      return 0;
}

219774E-Lowest Number

Code

#include<stdio.h>
int main()
{
     int n, i, x, min, pos=0;
     int arr[100010];
     scanf("%d", &n);
     for(i=1; i<=n; i++)
     {
         scanf("%d", &arr[i]);
     }
     for(i=1; i<=n; i++)
     {
         if(arr[i] < min)
         {
             min = arr[i];
             pos=i;
         }
     }
         printf("%d %d", min, pos);
     return 0;
}

219774F-Reversing

Code

#include<stdio.h>
int main()
{
     int n, i, x;
     int arr[100010];
     scanf("%d", &n);
     i=1;
     while(i<=n)
     {
         scanf("%d", &arr[i]);
         i++;
     }
     for(i=n; i>=1; i--)
     {
         printf("%d ", arr[i]);
     }
     return 0;
}

219774H-Sorting

Code

#include<stdio.h>
int main()
{
     int n, i, x;
     int arr[100010];
     scanf("%d", &n);
     i=1;
     while(i<=n)
     {
         scanf("%d", &arr[i]);
         i++;
     }
     for(i=n; i>=1; i--)
     {
         printf("%d ", arr[i]);
     }
     return 0;
}

219774L-Max Subarray

Code

#include<stdio.h>
int main()
{
    int n, i, x, j, a[10001], t, mx;
    scanf("%d", &t);
    while(t--)
    {
       scanf("%d", &n);
       for(i=0; i<n; i++)
       {
           scanf("%d", &a[i]);
       }

       for(i=0; i<n; i++)
       {
            mx=-100001;
            for(j=i; j<n; j++)
            {
                if(a[j] > mx)
                {
                    mx=a[j];
                }
                printf("%d ", mx);
            }
        }
        printf("\n");
    }
    return 0;
}

219774M-Replace MinMax

Code

#include<stdio.h>
int main()
{
   int n, i, j, min, max, temp;
   scanf("%d", &n);
   int arr[100010];

   for(i=1; i<=n; i++)
   {
       scanf("%d", &arr[i]);
   }

   min=arr[1], max=arr[1];
   for(i=1; i<=n; i++)
   {
       if(arr[i] < min)
       {
           min = arr[i];
       }
       if(arr[i] > max)
       {
           max = arr[i];
       }
   }

    for(i=1; i<=n; i++)
    {
        if(arr[i]==min){
            printf("%d ", max);
        }else if(arr[i]==max){
            printf("%d ", min);
        }else{
            printf("%d ", arr[i]);}
    }
     return 0;
}

219774S-Search In Matrix

Code

#include<stdio.h>
int main()
{
   int n, i, j, a[101][101], b[101][101], p, r, c, f;
   scanf("%d%d", &r, &c);

   for(i=1; i<=r; i++)
        for(j=1; j<=c; j++)
            scanf("%d", &a[i][j]);

   f=0;
   scanf("%d", &p);
   for(i=1; i<=r; i++)
   {
      for(j=1; j<=c; j++)
      {
         if(a[i][j] == p)
         {
            f=1;
            //break;
         }
      }
   }
   if(f==1)
   {
       printf("will not take number");
   }
   else
   {
       printf("will take number");
   }
     return 0;
}

219774V-Frequency Array

Code

#include<stdio.h>
int main()
{
   int arr[100001], i,j,x, m, n, cnt, freq[100001]={0}, val;
   scanf("%d%d", &n, &m);

   for(i=0; i<n; i++)
   {
       scanf("%d", &arr[i]);
   }
   for(i=0; i<n; i++)
   {
      //arr[i]=10
      val=arr[i];
      freq[val]++;
   }
   for(i=1; i<=m; i++)
   {
       printf("%d\n", freq[i]);
   }
   return 0;
}

219774Z-Binary Search

Code

--------------------------------------------------------------------

Try to solve this proble using with String:

219856C-Compare

Code

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int i, j, mn;
    string x, y;
    cin>>x>>y;
    if(x < y)
        cout<<x;
    else
        cout<<y;
    return 0;
}

219856F-Way Too Long Words

Code

#include<stdio.h>
#include<string.h>
int main()
{
    int i, n, len, x;
    scanf("%d", &n);
    char a[1000001];
    for(i=0; i<n; i++)
    {
      scanf("%s", a);
      x=strlen(a);

        if(x <= 10)
        {
            printf("%s\n", a);
        }
        else
        {
          printf("%c%d%c\n", a[0],x-2,a[x-1]);
        }
    }
   return 0;
}

219856H-Good or Bad

Code

#include<stdio.h>
#include<string.h>
int main()
{
   int n,i,j,x,t,f;
   scanf("%d", &n);
   char str[100001];
   for(i=0; i<n; i++)
   {
       scanf("%s",str);
       f=0;
       for(j=0; j<strlen(str)-2; j++)
       {
           if(str[j]=='0' && str[j+1]=='1' && str[j+2]=='0' || str[j]=='1' && str[j+1]=='0' && str[j+2]=='1')
           {
               f=1;
               break;
           }
       }

     if(f==1)
          printf("Good\n");
     else
          printf("Bad\n");
   }
    return 0;
}

219856J-Count Letters

Code

#include<stdio.h>
#include<string.h>
int main()
{
    char str[10000001];
    int i, hi[2000]={0};
    scanf("%s", str);

    for(i=0; str[i]!='\0'; i++)
    {
        hi[ str[i]]++;
    }
    for(i = 'a'; i <= 'z'; i++)
    {
        if(hi[i] > 0)
        {
            printf("%c : %d\n", i, hi[i]);
        }
    }
    return 0;
}

219856K-I Love strings

Code

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<math.h>
void call()
{
    int i,j,k;
    char s[100];
    char s1[100];

    scanf("%s%s", s, s1);
    if(strlen(s) < strlen(s1))
    {
        j = strlen(s);
        k = strlen(s1);
    }
    else
    {
        j = strlen(s1);
        k = strlen(s);
    }
    for(i=0; i < j; i++)
    {
        printf("%c", s[i]);
        printf("%c", s1[i]);
    }
    for(i = j; i < k; i++)
    {
        if(strlen(s) < strlen(s1))
        {
            printf("%c", s1[i]);
        }
        else printf("%c", s[i]);
    }
}
int main()
{
    int t, k;
    scanf("%d", &t);
    for(k=1; k<=t; k++)
    {
        call();
        printf("\n");;
    }
    return 0;
}

219856L-String Functions

Code

219856O-Sort String

Code

#include<stdio.h>
#include<string.h>
int main()
{
   int n,i,j,k,a[10001]={0};
   scanf("%d ", &n);
   char x;
   for(i=0; i<n; i++)
   {
       scanf("%c", &x);
       a[x]+=1;
   }
       for(i='a'; i<='z'; i++)
       {
           if(a[i]>0)
           {
               for(j=1; j<=a[i]; j++)
               {
                   printf("%c", i);
               }
           }
        }
   return 0;
}

219856R-String Score

Code

--------------------------------------------------------------------

Try to solve this proble using with Function:

223205D-Prime Function

Code

#include<stdio.h>
#include<math.h>
int isprime(int n)
{
   int i,f=0,x;
   if(n==1)
     return 1;
   x=sqrt(n);
   for(i=2; i<=x; i++)
   {
       if(n%i==0)
       {
          f=1;
          break; 
       }
   }
   return f;
}

int main()
{
   int a, x;
   scanf("%d", &a);
   while(a--)
   {
      scanf("%d", &x);
      if(isprime(x)==1)
          printf("NO\n");
      else
          printf("YES\n");
   }
   return 0;
}

22320E-Swap

Code

#include<stdio.h>
void reverse(int a, int b)
{
   int temp=0;
    temp=a;
    a=b;
    b=temp;
   printf("%d %d\n", a, b);
}

int main()
{
   int a, b, p;
   scanf("%d%d", &a, &b);
   reverse(a, b);
   return 0;
}

22320G-Max and MIN

Code

#include<stdio.h>
int mn(int arr[], int n)
{
   int i, y, mn=100001;
   for(i=1; i<=n; i++)
   {
       if(arr[i] < mn)
       {
           mn=arr[i];
       }
   }
   return mn;
}


int mx(int arr[], int n)
{
   int i, x, mx=-1;
   for(i=1; i<=n; i++)
   {
       if(arr[i] > mx)
       {
           mx=arr[i];
       }
   }
   return mx;
}
int main()
{
    int arr[100001], i, MIN, MAX, n, m, j;
    scanf("%d", &n);
    for(i=1; i<=n; i++)
    {
        scanf("%d", &arr[i]);
    }
    MIN=mn(arr,n);
    MAX=mx(arr,n);
    printf("%d %d\n",MIN, MAX);
    return 0;
}

22320K-Shift Right

Code

#include <iostream>
using namespace std;
void change(int arr[], int n, int k, int ans[])
{
    for(int i=0; i<n; i++)
    {
        int tmp = (i+k)%n;
        ans[tmp]=arr[i];
    }
    return;
}

int main()
{
    int n, k, i;
    cin >> n >> k;
    int arr[n], ans[n];
    for(i=0; i<n; i++)
        cin >> arr[i];
    change(arr, n, k, ans);
    for(i=0; i<n; i++)
        cout << ans[i] << " ";
}

---------------------------------------------------------------

Try to solve this proble using with Recurssion:

223339C-Print from N to 1

Code

#include<stdio.h>
int print(int i, int n)
{
    if(i>n)
        return 0;
        print(i+1, n);

        if(i==1)
           printf("%d", i);
        else
           printf("%d ", i);
}

int main()
{
    int n, i, x;
    scanf("%d", &n);

    print(1, n);
}

223339D-Print Digits using Recursion

Code

#include<stdio.h>
void digit(int x)
{
    if(x==0)
        return;
    digit(x/10);
    printf("%d ", x%10);

}

int main()
{
   int n, i, x;
   scanf("%d", &n);
   for(i=0; i<n; i++)
   {
       scanf("%d", &x);
       if(x==0)
       {
           printf("0\n");
       }
       else
       {
           digit(x);
           printf("\n");
       }
   }
   return 0;
}

223339E-Base Converssion

Code

#include<stdio.h>
void binary(int n)
{
   if(n==0)
      return;
   binary(n/2);
   printf("%d", n%2);
}

int main()
{
    int n, i, x;
    scanf("%d", &n);
    while(n--)
    {
        scanf("%d", &x);
        binary(x);
        printf("\n");
    }
    return 0;
}

223339J-Factorial

Code

#include<stdio.h>
long long int fact(int n);
int main()
{
    int result, n;
    scanf("%d", &n);
    printf("%lld\n", fact(n));
    return 0;

}

long long int fact(int n)
{
    if(n==1)
        return 1;
    else
        return n*fact(n-1);
}

Rev.	By	When	Δ	Comment
en96	arefin_hossain	2022-01-15 22:37:38	12
en95	arefin_hossain	2022-01-15 22:36:05	181
en94	arefin_hossain	2022-01-15 22:33:22	45
en93	arefin_hossain	2022-01-15 22:31:53	369
en92	arefin_hossain	2022-01-15 22:23:37	6067
en91	arefin_hossain	2022-01-14 09:18:38	3027
en90	arefin_hossain	2022-01-14 09:08:30	4342
en89	arefin_hossain	2022-01-13 21:49:56	5444
en88	arefin_hossain	2022-01-12 23:26:42	18
en87	arefin_hossain	2022-01-12 23:25:55	15
en86	arefin_hossain	2022-01-12 23:24:58	157
en85	arefin_hossain	2022-01-12 23:22:56	3851
en84	arefin_hossain	2022-01-12 23:06:47	157
en83	arefin_hossain	2022-01-12 23:04:45	224
en82	arefin_hossain	2022-01-12 23:03:04	78
en81	arefin_hossain	2022-01-12 23:01:09	86
en80	arefin_hossain	2022-01-12 23:00:05	87
en79	arefin_hossain	2022-01-12 22:59:08	9	Tiny change: 'DymW0hN)\n\n\n\n<h5>' -> 'DymW0hN)\n15 arrrra\n\n\n<h5>'
en78	arefin_hossain	2022-01-12 22:58:34	12
en77	arefin_hossain	2022-01-12 22:57:57	1477
en76	arefin_hossain	2022-01-12 22:51:07	1149	Tiny change: 'oblem/L)\n\n<spoiler' -> 'oblem/L)\n<spoiler' (published)
en75	arefin_hossain	2022-01-12 22:40:15	17	Tiny change: 'oblem/L)\n\n<spoiler' -> 'oblem/L)\n<spoiler' (saved to drafts)
en74	arefin_hossain	2022-01-12 22:34:01	5	Tiny change: 'oblem/L)\n\n<spoiler' -> 'oblem/L)\n<spoiler'
en73	arefin_hossain	2022-01-12 22:32:21	41
en72	arefin_hossain	2022-01-12 22:27:58	11
en71	arefin_hossain	2022-01-12 22:23:51	69	(published)
en70	arefin_hossain	2022-01-12 22:19:24	769	(saved to drafts)
en69	arefin_hossain	2022-01-12 22:05:49	4
en68	arefin_hossain	2022-01-12 22:04:35	504	(published)
en67	arefin_hossain	2022-01-12 21:55:23	187	(saved to drafts)
en66	arefin_hossain	2022-01-12 21:49:58	427
en65	arefin_hossain	2022-01-12 21:46:38	509
en64	arefin_hossain	2022-01-12 21:41:54	352
en63	arefin_hossain	2022-01-12 21:37:19	34
en62	arefin_hossain	2022-01-12 21:35:37	256
en61	arefin_hossain	2022-01-12 21:32:40	92
en60	arefin_hossain	2022-01-12 21:31:37	725
en59	arefin_hossain	2022-01-12 21:27:02	199
en58	arefin_hossain	2022-01-12 21:24:01	7
en57	arefin_hossain	2022-01-12 21:23:13	10
en56	arefin_hossain	2022-01-12 21:21:00	524
en55	arefin_hossain	2022-01-11 22:59:27	21	Reverted to en53
en54	arefin_hossain	2022-01-11 22:56:31	21	Reverted to en52
en53	arefin_hossain	2022-01-11 22:50:17	21	Tiny change: '="Code">\n<h6>\n #include<s' -> '="Code">\n <h6>#include<s'
en52	arefin_hossain	2022-01-11 22:48:32	64	Tiny change: '="Code">\n<h6>\n #include<s' -> '="Code">\n <h6>#include<s'
en51	arefin_hossain	2022-01-11 22:47:15	8	Tiny change: '="Code">\n<h6>\n #include<s' -> '="Code">\n <h6>#include<s'
en50	arefin_hossain	2022-01-11 22:46:03	7	Tiny change: '="Code">\n<h6>\n #include<s' -> '="Code">\n <h6>#include<s'
en49	arefin_hossain	2022-01-11 22:44:19	6	Tiny change: '="Code">\n<h6>\n #include<s' -> '="Code">\n <h6>#include<s'
en48	arefin_hossain	2022-01-11 22:43:49	185
en47	arefin_hossain	2022-01-11 22:42:20	27
en46	arefin_hossain	2022-01-11 22:41:36	9
en45	arefin_hossain	2022-01-11 22:39:50	137
en44	arefin_hossain	2022-01-11 22:38:34	0	for(i=1; i<=n-2; i++)\n{ c = a + b;\nprintf(" %d", c);\na = b;\nb = c;\n}
en43	arefin_hossain	2022-01-11 22:37:19	117	Tiny change: ', c, i, n;\n\n sc' -> ', c, i, n; \n\n sc'
en42	arefin_hossain	2022-01-11 22:32:26	11	Tiny change: ', c, i, n;\n\n sc' -> ', c, i, n; \n\n sc'
en41	arefin_hossain	2022-01-11 22:28:47	4	Tiny change: ', c, i, n;\n\n sc' -> ', c, i, n; \n\n sc'
en40	arefin_hossain	2022-01-11 22:28:16	4	Tiny change: ', c, i, n;\n\n sc' -> ', c, i, n; \n\n sc'
en39	arefin_hossain	2022-01-11 22:27:40	7	Tiny change: ', c, i, n;\n\n sc' -> ', c, i, n; \n\n sc'
en38	arefin_hossain	2022-01-11 22:27:00	213	\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
en37	arefin_hossain	2022-01-11 22:24:00	16
en36	arefin_hossain	2022-01-11 22:22:20	26	Tiny change: '"aaa">\n<h1>stdio.h</h1>\n\n</spo' -> '"aaa">\n<h6>stdio.h</h6>\n\n</spo'
en35	arefin_hossain	2022-01-11 22:18:57	168	Tiny change: '"aaa">\n<h1>stdio.h</h1>\n\n</spo' -> '"aaa">\n<h6>stdio.h</h6>\n\n</spo'
en34	arefin_hossain	2022-01-11 22:17:38	4	Tiny change: '"aaa">\n<h1>stdio.h</h1>\n\n</spo' -> '"aaa">\n<h6>stdio.h</h6>\n\n</spo'
en33	arefin_hossain	2022-01-11 22:17:15	12
en32	arefin_hossain	2022-01-11 22:16:11	54
en31	arefin_hossain	2022-01-11 22:13:46	4
en30	arefin_hossain	2022-01-11 22:13:01	1414
en29	arefin_hossain	2022-01-11 22:10:26	1194
en28	arefin_hossain	2022-01-11 22:08:57	219
en27	arefin_hossain	2022-01-11 22:06:40	34
en26	arefin_hossain	2022-01-11 22:04:52	44
en25	arefin_hossain	2022-01-11 22:03:45	368
en24	arefin_hossain	2022-01-11 22:00:41	480
en23	arefin_hossain	2022-01-11 21:58:46	79
en22	arefin_hossain	2022-01-11 21:57:52	51
en21	arefin_hossain	2022-01-11 21:56:15	385
en20	arefin_hossain	2022-01-11 21:54:36	22
en19	arefin_hossain	2022-01-11 21:53:49	94
en18	arefin_hossain	2022-01-11 21:48:30	7
en17	arefin_hossain	2022-01-11 21:47:31	5
en16	arefin_hossain	2022-01-11 21:45:47	106
en15	arefin_hossain	2022-01-11 21:43:36	11
en14	arefin_hossain	2022-01-11 21:39:52	74
en13	arefin_hossain	2022-01-11 21:38:47	16	Tiny change: ' Fibonacci](219432Y)\n\n\n\n\n' -> ' Fibonacci:219432Y - 14]\n\n\n\n\n'
en12	arefin_hossain	2022-01-11 21:37:25	38
en11	arefin_hossain	2022-01-11 21:34:22	402
en10	arefin_hossain	2022-01-11 21:32:15	407
en9	arefin_hossain	2022-01-11 21:30:22	540
en8	arefin_hossain	2022-01-11 21:27:10	81
en7	arefin_hossain	2022-01-11 21:26:22	137
en6	arefin_hossain	2022-01-11 21:24:04	73
en5	arefin_hossain	2022-01-11 21:18:18	34
en4	arefin_hossain	2022-01-11 21:15:10	64
en3	arefin_hossain	2022-01-11 21:10:03	386
en2	arefin_hossain	2022-01-11 21:07:17	102	(published)
en1	arefin_hossain	2022-01-11 19:56:43	1073	Initial revision (saved to drafts)

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