Submission #1248056

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Source Code Expand

#include <bits/stdc++.h>
using namespace std;

#define pb         push_back

typedef long long ll;
const ll INF = 1000000000000000000ll;
const ll MOD = 1000000007ll;
const double EPS = 1e-8;

int sum[100005];

int main(void) {
	//ios_base::sync_with_stdio(false);
	//cin.tie(0);
	int n, k;
	cin >> n >> k;

	vector<int> a;
	for(int i=0; i<n; i++){
		int t;
		cin >> t;
		a.pb(t);
		if(i == 0){
			sum[i] = t;
		}else{
			sum[i] = sum[i-1] + t;
		}
	}

	ll ans = 0;
	for(int i=0; i<n-k+1; i++){
		if(i == 0){
			ans += sum[i+k-1];
		}else{
			ans += sum[i+k-1] - sum[i-1];
		}
	}

	cout << ans << endl;

	
	return 0;
}

Submission Info

Judge Result