Submission #1407773

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Source Code Expand

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

#define rep(i, n) for (int i = 0; i < (n); i ++)
#define int long long

singed main() {
        int n;
        cin >> n;
        vector<int> d(n);
        rep(i, n) cin >> d[i];
        sort(d.begin(), d.end());
        vector<int> x(n, 0);
        rep(i, n) {
                auto it = lower_bound(d.begin(), d.end(), 2 * d[i]);
                x[i] = d.end() - it;
        }
        for (int i = x.size() -  1; i > 0; i --) {
                x[i - 1] += x[i];
        }
        vector<int> y(n, 0);
        rep(i, n) {
                auto it = lower_bound(d.begin(), d.end(), 2 * d[i]);
                int p = it - d.begin();
                if (p == n) y[i] = 0;
                else y[i] = x[p];
        }
        for (int i = y.size() - 1; i > 0; i --) y[i - 1] += y[i];
        long long ans = 0;
        rep(i, n) {                
                auto it = lower_bound(d.begin(), d.end(), 2 * d[i]);
                int p = it - d.begin();
                ans += y[p];
        }
        cout << ans << endl;
        return 0;
}

Submission Info

Compile Error

./Main.cpp:7:1: error: ‘singed’ does not name a type
 singed main() {
 ^