I was solving this problem [Problem Link](https://codeforces.net/contest/160/problem/D)↵
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<spoiler summary="Here is my code">↵
↵
~~~~~↵
#include <bits/stdc++.h>↵
using namespace std;↵
signed main(){↵
ios_base::sync_with_stdio(false);↵
cin.tie(0);↵
/* -1 -> None↵
0 -> at least one↵
1 -> any↵
-2 -> undecided↵
*/↵
int N,M; cin >> N >> M;↵
vector<tuple<int,int,int,int>> e(M);↵
vector<int> answer(M, -2);↵
vector<int> p(N), sz(N, 1);↵
iota(p.begin(), p.end(), 0);↵
↵
function<int(int)> find = [&](int x){↵
return (x == p[x] ? x : p[x] = find(x));↵
};↵
function<bool(int,int)> unite = [&](int x, int y){↵
x = find(x); y = find(y);↵
if(x != y){↵
if(sz[x] < sz[y]) swap(x, y);↵
p[y] = x;↵
sz[x] += sz[y];↵
return true;↵
}↵
return false;↵
};↵
for(int i = 0; i < M; i++){↵
int x,y,z; cin >> x >> y >> z;↵
x--; y--;↵
e[i] = make_tuple(z, x, y, i);↵
}↵
sort(e.begin(), e.end());↵
int i = 0;↵
while(i < M){↵
int j = i;↵
while(j < M && get<0>(e[j]) == get<0>(e[i])){↵
if(find(get<1>(e[j])) == find(get<2>(e[j])))↵
answer[get<3>(e[j])] = -1;↵
++j;↵
}↵
bool ok = true;↵
j = i;↵
while(j < M && get<0>(e[j]) == get<0>(e[i])){↵
if(answer[get<3>(e[j])] == -1){↵
++j; continue;↵
}↵
if(unite(get<1>(e[j]), get<2>(e[j])) == false) // When I comment this line↵
ok = false;↵
++j;↵
}↵
j = i;↵
while(j < M && get<0>(e[j]) == get<0>(e[i])){↵
if(answer[get<3>(e[j])] == -1){↵
++j; continue;↵
}↵
if(ok) answer[get<3>(e[j])] = 1;↵
else answer[get<3>(e[j])] = 0;↵
++j;↵
}↵
i = j;↵
}↵
for(int i = 0; i < M; i++){↵
if(answer[i] == -1)↵
cout << "none" << '\n';↵
else if(answer[i] == 0)↵
cout << "at least one" << '\n';↵
else↵
cout << "any" << '\n';↵
}↵
return 0;↵
}↵
↵
~~~~~↵
↵
↵
</spoiler>↵
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Now I don't want to know the logic of how to solve the problem or whether my logic is wrong or not. ↵
↵
It's just that when I am compiling this code is giving RE (Specifically : Runtime error: exit code is 2147483647)↵
↵
Now when I comment out the line in which I unite two sets (Mentioned in the code), it does not give RE.↵
↵
But I don't know how can my unite function be wrong(It's just merging two sets [DSU]). ↵
↵
Can anyone tell me the flaw?↵
↵
ThanksEDIT : Found the error. Tbh it was a silly one. In my unite function when (p[x] != x) I call the function again with the same argument instead of p[x].
↵
<spoiler summary="Here is my code">↵
↵
~~~~~↵
#include <bits/stdc++.h>↵
using namespace std;↵
signed main(){↵
ios_base::sync_with_stdio(false);↵
cin.tie(0);↵
/* -1 -> None↵
0 -> at least one↵
1 -> any↵
-2 -> undecided↵
*/↵
int N,M; cin >> N >> M;↵
vector<tuple<int,int,int,int>> e(M);↵
vector<int> answer(M, -2);↵
vector<int> p(N), sz(N, 1);↵
iota(p.begin(), p.end(), 0);↵
↵
function<int(int)> find = [&](int x){↵
return (x == p[x] ? x : p[x] = find(x));↵
};↵
function<bool(int,int)> unite = [&](int x, int y){↵
x = find(x); y = find(y);↵
if(x != y){↵
if(sz[x] < sz[y]) swap(x, y);↵
p[y] = x;↵
sz[x] += sz[y];↵
return true;↵
}↵
return false;↵
};↵
for(int i = 0; i < M; i++){↵
int x,y,z; cin >> x >> y >> z;↵
x--; y--;↵
e[i] = make_tuple(z, x, y, i);↵
}↵
sort(e.begin(), e.end());↵
int i = 0;↵
while(i < M){↵
int j = i;↵
while(j < M && get<0>(e[j]) == get<0>(e[i])){↵
if(find(get<1>(e[j])) == find(get<2>(e[j])))↵
answer[get<3>(e[j])] = -1;↵
++j;↵
}↵
bool ok = true;↵
j = i;↵
while(j < M && get<0>(e[j]) == get<0>(e[i])){↵
if(answer[get<3>(e[j])] == -1){↵
++j; continue;↵
}↵
if(unite(get<1>(e[j]), get<2>(e[j])) == false) // When I comment this line↵
ok = false;↵
++j;↵
}↵
j = i;↵
while(j < M && get<0>(e[j]) == get<0>(e[i])){↵
if(answer[get<3>(e[j])] == -1){↵
++j; continue;↵
}↵
if(ok) answer[get<3>(e[j])] = 1;↵
else answer[get<3>(e[j])] = 0;↵
++j;↵
}↵
i = j;↵
}↵
for(int i = 0; i < M; i++){↵
if(answer[i] == -1)↵
cout << "none" << '\n';↵
else if(answer[i] == 0)↵
cout << "at least one" << '\n';↵
else↵
cout << "any" << '\n';↵
}↵
return 0;↵
}↵
↵
~~~~~↵
↵
↵
</spoiler>↵
↵
Now I don't want to know the logic of how to solve the problem or whether my logic is wrong or not. ↵
↵
It's just that when I am compiling this code is giving RE (Specifically : Runtime error: exit code is 2147483647)↵
↵
Now when I comment out the line in which I unite two sets (Mentioned in the code), it does not give RE.↵
↵
But I don't know how can my unite function be wrong(It's just merging two sets [DSU]). ↵
↵
Can anyone tell me the flaw?↵
↵
