【HDOJ】1421 搬寝室

DP。这题都能TLE，发现memset有时居然比for还要慢。

 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>

 #define MAXN 2005
 #define INF  0x3fffffff
 int dp[MAXN][MAXN];
 int buf[MAXN];
 int deg[MAXN];

 int mymin(int a, int b) {
     return (a<b) ? a:b;
 }

 int comp(const void *a, const void *b) {
     return *(int *)a - *(int *)b;
 }

 int main() {
     int n, m, k;
     int i, j;

     while (scanf("%d %d", &n, &k) != EOF) {
         for (i=; i<=n; ++i)
             scanf("%d", &buf[i]);
         qsort(buf+, n, sizeof(int), comp);
         m = ;
         for (i=; i<=n; ++i)
             deg[m++] = (buf[i]-buf[i-])*(buf[i]-buf[i-]);

         for (i=; i<=n; ++i) {
             dp[i][] = ;
             for (j=; j<=k; ++j) {
                 dp[i][j] = INF;
             }
         }

         for (i=; i<=n; ++i) {
             for (j=; j+j<=i; ++j) {
                 dp[i][j] = mymin(dp[i-][j-]+deg[i-], dp[i-][j]);
             }
         }
         printf("%d\n", dp[n][k]);
     }

     return ;
 }