51Nod 1065 最小正子段和

#include <iostream>
#include <algorithm>

using namespace std;
const int maxn = 50000 + 5;
struct node{
    long long x;
    int id;
}a[maxn];

bool cmp(node xx, node yy){
    if (xx.x == yy.x)
        return xx.id < yy.id;
    else return xx.x < yy.x;
}

int main(){
    ios::sync_with_stdio(false);
    int n;
    cin >> n;
    int xx;
    a[0].id = 0;
    a[0].x = 0;
    for (int i = 1; i <= n; i++){
        cin >> xx;
        a[i].x = a[i - 1].x + xx;
        a[i].id = i;
    }
    sort(a, a + n + 1, cmp);
    long long ans;
    bool flag = true;
    for (int i = 1; i <= n; i++){
        if (a[i].x - a[i - 1].x > 0 && a[i].id - a[i - 1].id > 0){
            if (flag){
                ans = a[i].x - a[i - 1].x;
                flag = false;
            }
            else{
                ans = min(ans, a[i].x - a[i - 1].x);
            }
        }
    }
    cout << ans << endl;
    system("pause");
    return 0;
}