[luoguP1877] [HAOI2012]音量调节（DP）

传送门

绝世傻DP

#include <cstdio>
#include <iostream>
#define N 51

int n, s, mx;
bool f
[1001];

inline int read()
{
int x = 0, f = 1;
char ch = getchar();
for(; !isdigit(ch); ch = getchar()) if(ch == '-') f = -1;
for(; isdigit(ch); ch = getchar()) x = (x << 1) + (x << 3) + ch - '0';
return x * f;
}

int main()
{
int i, j, k, x;
n = read();
s = read();
mx = read();
f[0][s] = 1;
for(i = 1; i <= n; i++)
{
x = read();
for(j = 0; j <= mx; j++)
{
if(j + x <= mx && f[i - 1][j]) f[i][j + x] = 1;
if(j - x >= 0 && f[i - 1][j]) f[i][j - x] = 1;
}
}
for(i = mx; i >= 0; i--)
if(f
[i])
{
printf("%d\n", i);
return 0;
}
puts("-1");
return 0;
}