提出 #71466632

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ソースコード 拡げる

#include <bits/stdc++.h>

#include <atcoder/all>

using namespace std;
using namespace atcoder;

#define int long long
#define ALL(x) (x).begin(), (x).end()
#define MAX(x) *max_element(ALL(x))
#define MIN(x) *min_element(ALL(x))

typedef pair<int, int> PI;
typedef pair<int, pair<int, int>> PII;
static const int INF = 1010000000000000017LL;
static const double eps = 1e-12;
static const double pi = 3.14159265358979323846;
static const int dx[4] = {1, -1, 0, 0};
static const int dy[4] = {0, 0, 1, -1};
static const int ddx[8] = {1, -1, 0, 0, 1, 1, -1, -1};
static const int ddy[8] = {0, 0, 1, -1, 1, -1, 1, -1};

template <class T>
inline bool chmin(T& a, T b) {
    if (a > b) {
        a = b;
        return true;
    }
    return false;
}
template <class T>
inline bool chmax(T& a, T b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}

int N;

signed main() {
    cin >> N;
    cout << N * (N + 1) / 2 << endl;
}

提出情報

ジャッジ結果