题解 | 分割等和子集

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

int main() {
    int n;
    cin >> n;
    vector<int> a(n);
    long long sum = 0;
    for (int i = 0; i < n; ++i) {
        cin >> a[i];
        sum += a[i];
    }

    if (sum & 1) {
        cout << "false\n";
        return 0;
    }
    int target = sum / 2;
    // sum 最大 50000，target ≤ 25000
    bitset<50001> dp;
    dp[0] = 1;
    for (int v : a) dp |= (dp << v);

    cout << (dp[target] ? "true\n" : "false\n");
    return 0;
}