POJ 2185 Milking Grid

 1 #include <iostream>
 2 #include <cstdio>
 3 #include <cstring>
 4 #include <cmath>
 5 #include <algorithm>
 6 #include <climits>
 7 #include <vector>
 8 #include <queue>
 9 #include <cstdlib>
10 #include <string>
11 #include <set>
12 #include <stack>
13 #define LL long long
14 #define pii pair<int,int>
15 #define INF 0x3f3f3f3f
16 using namespace std;
17 int row,col,fail[10100],x,y;
18 char str[10010][80];
19 bool cmp(int a,int b){
20     for(int i = 0; i < row; i++)
21         if(str[i][a] != str[i][b]) return false;
22         return true;
23 }
24 int main() {
25     while(~scanf("%d %d",&row,&col)){
26         for(int i = 0; i < row; i++)
27             scanf("%s",str[i]);
28         fail[0] = fail[1] = 0;
29         for(int i = 1; i < row; i++){
30             int j = fail[i];
31             while(j && strcmp(str[i],str[j])) j = fail[j];
32             if(!strcmp(str[i],str[j])) fail[i+1] = j+1;
33             else fail[i+1] = 0;
34         }
35         x = row - fail[row];
36         fail[0] = fail[1] = 0;
37         for(int i = 1; i < col; i++){
38             int j = fail[i];
39             while(j && !cmp(i,j)) j = fail[j];
40             if(cmp(i,j)) fail[i+1] = j+1;
41             else fail[i+1] = 0;
42         }
43         y = col - fail[col];
44         printf("%d\n",x*y);
45     }
46     return 0;
47 }