[DP]bzoj1037 - cool's Blog
[DP]bzoj1037
cool
posted @ 2015年10月07日 15:55
in DP
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话说我的DP真的好水 这种题目根本做不出
f[i][j][x][y] 表示 总共i人 有j个男的 从i人往前的一段人中，男比女最多多x人 女比男最多做y人
这是 网上的题解 代码如下
f[0][0][0][0] = 1;
for (int i = 0;i < n+m;i++)
for (int j = 0;j <= n;j++)
for (int x = 0;x <= k;x++)
for (int y = 0;y <= k;y++)
if (f[i][j][x][y])
{
if (x + 1 <= k&&j+1 <= n)
f[i+1][j+1][x+1][max(y-1,0)] += f[i][j][x][y],f[i+1][j+1][x+1][max(y-1,0)] %= mod;
if (y + 1 <= k&&i+1-j <= m)
f[i+1][j][max(x-1,0)][y+1] += f[i][j][x][y],f[i+1][j][max(x-1,0)][y+1] %= mod;
}
但有点让我想不通 为什么不干脆f[i][j][x][y] i表示男 j表示女呢 而且空间 时间都快了。
而且在bz上也AC了 请大神教导
2022年9月16日 22:32
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