SCU2016-02 M题 （dp）

水dp无话可说

#include <cstdio>
#include <cstring>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;
#define pr(x) cout << #x << ": " << x << "  " 
#define pl(x) cout << #x << ": " << x << endl;

const int maxn = 500 + 5;  
int c[maxn], res[maxn], dp[maxn][maxn];  
int main()  
{  
    int n, K;  
    scanf("%d%d", &n, &K);  
    for(int i = 0; i < n; ++i){  
        scanf("%d", &c[i]);  
    }  
    sort(c, c + n);  
    memset(dp, 0, sizeof(dp));  
    dp[0][0] = 1;  
    for(int i = 0; i < n; ++i){  
        for(int j = K; j >= c[i]; --j){  
            for(int k = 0; k + c[i] <= K; ++k){  
                if(dp[j - c[i]][k]) dp[j][k] = dp[j][k + c[i]] = 1;  
            }  
        }  
    }  
    int ans = 0;  
    for(int i = 0; i <= K; ++i)  
        if(dp[K][i]) res[ans++] = i;  
    printf("%d\n", ans);  
    for(int i = 0; i < ans; ++i){  
        printf("%d%c", res[i], (i == (ans - 1) ? '\n' : ' '));  
    }  
    return 0;  
}