【HDOJ】2195 Monotone SE Min

简单DP。将[0,1]的浮点数离散化为[0,1000]的整数。最后再除以1000^2.

 /* 2195 */
 #include <cstdio>
 #include <cstring>
 #include <cstdlib>

 #define MAXN 1000
 #define MAXL 205
 #define INF  0xfffffff

 int dp[MAXL][MAXN+];
 char s[MAXL];

 int main() {
     int len;
     int i, j, k;
     int bi, tmp;
     double ans;

     #ifndef ONLINE_JUDGE
         freopen("data.in", "r", stdin);
     #endif

     while (scanf("%s", s) != EOF) {
         len = strlen(s);
         bi = (s[]=='') ? :MAXN;
         for (j=; j<=MAXN; ++j) {
             dp[][j] = (j-bi)*(j-bi);
         }
         for (i=; i<len; ++i) {
             bi = (s[i]=='') ? :MAXN;
             tmp = INF;
             for (j=; j<=MAXN; ++j) {
                 if (dp[i-][j] < tmp)
                     tmp = dp[i-][j];
                 dp[i][j] = tmp + (j-bi)*(j-bi);
             }
         }
         tmp = INF;
         i = len-;
         for (j=; j<=MAXN; ++j)
             if (dp[i][j] < tmp)
                 tmp = dp[i][j];
         ans = tmp / 1000000.0;
         printf("%.3lf\n", ans);
     }

     return ;
 }