题解 | #数组分组#

#include <iostream>
#include <vector>
using namespace std;
int n;
vector<int> v;
int sum = 0;
bool success = false;

void dfs(int idx, int l, int r)
{
    if(idx == n)
    {
        if(l == sum / 2)
            success = true;
        return;
    }

    if(v[idx] % 5 == 0)
        dfs(idx + 1, l + v[idx], r);
    else if(v[idx] % 3 == 0)
        dfs(idx + 1, l, r + v[idx]);
    else
    {
        dfs(idx + 1, l + v[idx], r);
        dfs(idx + 1, l, r + v[idx]);
    }    
}


int main()
{
    cin >> n;
    v.resize(n);
    for(int i = 0; i < n; i++) 
    {
        cin >> v[i];
        sum += v[i];
    }
    if(sum % 2)
    {
        puts("false");
        return 0;
    }
    dfs(0,0,0);
    if(success) puts("true");
    else puts("false");
    return 0;
}