I was solving this.

I encountered a problem while using std::accumulate.

I noticed that accumulate(v.begin(), v.end(), 0L) behaves differently in sublimText/Ideone and Codeforces.

for example,

int main() {
vector<long long> v{1,-1000000000,1,-1000000000,1,-1000000000};
long long sum = accumulate(v.begin(), v.end(), 0L);
cout<<sum;
}

in sublimeText or Ideone: prints -2999999997 and in Codeforces prints 1294967299.

you can try running this here

AC solution

Wrong solution

however, when 0L is changed to 0LL in accumulate function, both sublime text and CF returns the right sum (-2999999997)

is this expected? can someone help me understand this weird behavior?