tyvj1114 搭建双塔

#include<iostream>
#include<cstdio>
#include<string>
#include<cstring>
#include<algorithm>
using namespace std;
int n,a[105],f[105][2005];
int main(){
    cin>>n;
    for(int i = 1;i <= n;i++) scanf("%d",&a[i]);
    for(int i = 0;i <= n;i++){
        for(int j = 0;j <= 2000;j++){
            f[i][j] = -1;
        }
    }
    f[0][0] = 0;
    for(int i = 1;i <= n;i++){
        for(int j = 0;j <= 2000;j++){
            f[i][j] = max(f[i][j],f[i-1][j]);
            if(f[i-1][j] != -1){
                f[i][j+a[i]] = max(f[i][j+a[i]],f[i-1][j]);
                if(a[i] <= j) f[i][j-a[i]] = max(f[i][j-a[i]],f[i-1][j] + a[i]);
                else f[i][a[i]-j] = max(f[i][a[i]-j],f[i-1][j] + j);
            }
        }
    }
    if(f[n][0]) cout<<f[n][0];
    else cout<<"Impossible";
    return 0;
}