[luoguP2875] [USACO07FEB]牛的词汇The Cow Lexicon（DP）

传送门

f[i] 表示前 i 个字符去掉多少个 的最优解

直接暴力DP

——代码

 #include <cstdio>
 #include <cstring>
 #include <iostream>

 int n, m, cnt, f[];
 char s[], a[][];

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

 inline int min(int x, int y)
 {
     return x < y ? x : y;
 }

 int main()
 {
     int i, j, k, l;
     n = read();
     m = read();
     scanf("%s", s + );
     for(i = ; i <= n; i++) scanf("%s", a[i] + );
     for(i = ; i <= m; i++)
     {
         f[i] = i;
         for(j = ; j <= n; j++)
         {
             cnt = ;
             l = strlen(a[j] + );
             for(k = i; k; k--)
             {
                 if(a[j][l] == s[k]) l--;
                 else cnt++;
                 if(!l) break;
             }
             if(k) f[i] = min(f[i], f[k - ] + cnt);
         }
     }
     printf("%d\n", f[m]);
     return ;
 }