14246번: K보다 큰 구간 ↗

#include <bits/stdc++.h>

#define for1(s,n) for(int i = s; i < n; i++)
#define for1j(s,n) for(int j = s; j < n; j++)
#define foreach(k) for(auto i : k)
#define foreachj(k) for(auto j : k)
#define pb(a) push_back(a)
#define sz(a) a.size()

using namespace std;
typedef unsigned long long ull;
typedef long long ll;
typedef vector <int> iv1;
typedef vector <vector<int> > iv2;
typedef vector <ll> llv1;
typedef unsigned int uint;
typedef vector <ull> ullv1;
typedef vector <vector <ull> > ullv2;

ll N;
ll ar[110000];
ll K;
ll ans;


int main() {
  ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);

  cin >> N;
  for1(0, N) {
    cin >> ar[i];
  }
  cin >> K;

  ll a = 0;
  ll b = 1;
  ll s = ar[0];

  while(a < N && b <= N) {
    if(s > K) {
      ans += (N - b + 1);
      s -= ar[a];
      a++;
    } else {
      s += ar[b];
      b++;
    }
  }

  cout << ans;
}