UVA - 10604Chemical Reaction(记忆化搜索）

题目大意：UVA - 10604Chemical Reaction(记忆化搜索）

题目大意：给出N支试管，每支试管中都放一种化学药物，现在要求这些试管两两反应，产生新的化学药物。最后会只剩下一支试管有药物。这样的过程中会放热和吸热，问怎样安排反反应的顺序可以使得释放的热量最少。

解题思路：因为最多只有6种药品，并且最多十支试管，那么开个6维的数组，11*11*11*11*11还是可以的。然后目前剩下什么药物就能够决定释放热量的最好情况。

代码：

#include <cstdio>#include <cstring>#include <cstdlib>const int N = 11;const int M = 7;const int INF = 0x3f3f3f3f; int table[M][M];int heat[M][M];int f[N][N][N][N][N][N];int n, m;int Min (const int a, const int b) {return a < b ? a: b; }int judge (int *c) {int count1 = 0;int count2 = 0;for (int i = 0; i < m; i++) {if (!c[i])count1++;if (c[i] == 1)count2++;}if (count1 == m - 1 && count2 == 1)return 1;return 0;}void init () {for (int i = 0; i <= n; i++)for (int j = 0; j <= n; j++)for (int k = 0; k <= n; k++)for (int l = 0; l <= n; l++)for (int p = 0; p <= n; p++)for (int q = 0; q <= n; q++)f[i][j][k][l][p][q] = INF; }int dp (int *c) {int& ans = f[c[0]][c[1]][c[2]][c[3]][c[4]][c[5]];/*for (int i = 0; i < m; i++)printf ("%d ", c[i]);printf ("\n");*/if (ans != INF)return ans;if (judge(c) == 1)return ans = 0;int newc;for (int i = 0; i < m; i++) {if (c[i]) {c[i]--;for (int j = 0; j < m; j++) {if (c[j]) {c[j]--;newc = table[i + 1][j + 1] - 1;c[newc]++;ans = Min (ans, dp(c) + heat[i + 1][j + 1]);c[j]++;c[newc]--;}}c[i]++;}}return ans;}int main () {int t;int x;char str[M];int c[M];scanf ("%d", &t);while (t--) {scanf ("%d", &m);for (int i = 1; i <= m; i++)for (int j = 1; j <= m; j++) scanf ("%d%d", &table[i][j], &heat[i][j]);scanf ("%d", &n);memset (c, 0, sizeof (c));for (int i = 0; i < n; i++) {scanf ("%d", &x);c[x - 1]++;}scanf ("%s", str);init();printf ("%d\n", dp(c));}}