Hey everyone, I am looking for a team I can join for hash code. This is my first hash code so I will learn a lot.

If anyone has space in their team let me know, or If someone wanna join mine, hit me a dm.

Thanks.

PROBLEM

So I came across this problem and I would like to implement and idea that after removing values that are directly divisible by 3 and the pairs that add upto sum (divisible by 3), the rem. ones may have some kind of combination of elements with sum adding upto 3

Example:

arr = [1,1,1,1,1,2,2]

after two operations , pairs gets out [1,2],[1,2] with sum(%3==0)

rem = [1,1,1]

Now, how to know that rem array may have some combinations sum divisible by 3?

I have tried sieve and segmented sieve too but they are slow. Can anyone provide code to print primes till 10^9 FAST?

Python code would be a great help.

This is the question Link

There is a diff of 2. Can anyone look why my code is wrong?

a = int(input())

def solve(t):
    coins = 0
    for i in range(len(t)):
        if t[i]==1 or t[i] ==-1:
            pass
        else:
            if t[i]<0:
                coins+=-1 - t[i]
                t[i] = -1
            elif t[i]>0:
                coins += t[i] - 1
                t[i] = 1
            else:
                coins+=1
                t[i] += 1

    less = 0
    great = 0
    for i in t:
        if i<0:
            less+=1
        else:
            great+=1    


    # print(coins)
    if less&1!=0:
        #odd
        coins+=2

    return print(coins)    

t = list(map(int, input().strip().split()))
solve(t)

Hey everyone, I just wanted to ask any roadmap which I can follow to become great like you guys in cp. I know everything is achieved by practice but I wanna know what to practice and what resources to look up to.

Can anyone suggest some good tips???