Codeforces 475 B Strongly Connected City【DFS】

 1 #include<iostream>  
 2 #include<cstdio>  
 3 #include<cstring> 
 4 #include <cmath> 
 5 #include<stack>
 6 #include<vector>
 7 #include<map> 
 8 #include<set>
 9 #include<queue> 
10 #include<algorithm>  
11 #define mod=1e9+7;
12 using namespace std;
13 
14 typedef long long LL;
15 const int INF = 0x7fffffff;
16 const int maxn=105;
17 char s1[maxn],s2[maxn];
18 int cnt[maxn][maxn],vis[maxn][maxn];
19 int n,m;
20 
21 void dfs(int x,int y){
22     if(x<1||x>n||y<1||y>m) return;
23     if(vis[x][y]) return;
24     vis[x][y]=1;
25     cnt[x][y]++;
26     if(s1[x]==‘>‘) dfs(x,y+1);
27     if(s1[x]==‘<‘) dfs(x,y-1);
28     if(s2[y]==‘v‘) dfs(x+1,y);
29     if(s2[y]==‘^‘) dfs(x-1,y);
30 }
31 
32 int main(){
33     int i,j;
34     scanf("%d %d",&n,&m);
35     cin>>(s1+1);
36     cin>>(s2+1);
37     
38     
39     memset(cnt,0,sizeof(cnt));
40     
41     for(i=1;i<=n;i++){
42         for(j=1;j<=m;j++){
43                 memset(vis,0,sizeof(vis));
44                 dfs(i,j);
45         }    
46     }
47     
48     //for(i=1;i<=n;i++){
49     //    for(j=1;j<=m;j++)
50     //    printf("cnt[%d][%d]=%d\n",i,j,cnt[i][j]);
51     //}
52     
53     for(i=1;i<=n;i++){
54         for(j=1;j<=m;j++){
55             if(cnt[i][j]!=cnt[1][1]){
56                 printf("NO\n");
57                 return 0;
58             }
59         }        
60     }
61     
62     printf("YES\n");
63     return 0;    
64 }