拔河 参考代码

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

typedef long long LL;
const int maxn = 1000 + 100;
int n;
LL ans;
map<LL, int> cnt;
map<LL, int>::iterator it;
LL sum[maxn];

void add(LL x) {
    ++cnt[x];
}

void del(LL x) {
    it = cnt.find(x);
    if (it == cnt.end()) {
        return ;
    }
    if (it->second == 1) {
        cnt.erase(it);
        return ;
    }
    --it->second;
}

LL solve(LL x) {
    LL ret = 1e18;
    it = cnt.lower_bound(x);
    if (it != cnt.end()) {
        ret = min(ret, it->first - x);
    }
    if(it != cnt.begin()) {
        --it;
        ret = min(ret, x - it->first);
    }
    return ret;
}

int main() {
#ifdef ExRoc
    freopen("test.txt", "r", stdin);
#endif
    ios::sync_with_stdio(false);

    cin >> n;
    for (int i = 1; i <= n; ++i) {
        cin >> sum[i];
        sum[i] += sum[i - 1];
    }
    for (int i = 1; i <= n; ++i) {
        for (int j = i; j <= n; ++j) {
            add(sum[j] - sum[i - 1]);
        }
    }
    ans = 1e18;
    for (int i = 1; i < n; ++i) {
        for (int j = i; j <= n; ++j) {
            del(sum[j] - sum[i - 1]);
        }
        for (int j = i; j >= 1; --j) {
            ans = min(ans, solve(sum[i] - sum[j - 1]));
        }
    }
    cout << ans << endl;

    return 0;
}