#include<iostream>

 #include<cstdio>

 #include<cstring>

 #include <cmath>

 #include<stack>

 #include<vector>

 #include<map>

 #include<set>

 #include<queue>

 #include<algorithm>

 #define mod=1e9+7;

 using namespace std;

 typedef long long LL;

 const int INF = 0x7fffffff;

 const int maxn=;

 char s1[maxn],s2[maxn];

 int cnt[maxn][maxn],vis[maxn][maxn];

 int n,m;

 void dfs(int x,int y){

     if(x<||x>n||y<||y>m) return;

     if(vis[x][y]) return;

     vis[x][y]=;

     cnt[x][y]++;

     if(s1[x]=='>') dfs(x,y+);

     if(s1[x]=='<') dfs(x,y-);

     if(s2[y]=='v') dfs(x+,y);

     if(s2[y]=='^') dfs(x-,y);

 }

 int main(){

     int i,j;

     scanf("%d %d",&n,&m);

     cin>>(s1+);

     cin>>(s2+);

     memset(cnt,,sizeof(cnt));

     for(i=;i<=n;i++){

         for(j=;j<=m;j++){

                 memset(vis,,sizeof(vis));

                 dfs(i,j);

         }

     }

     //for(i=1;i<=n;i++){

     //    for(j=1;j<=m;j++)

     //    printf("cnt[%d][%d]=%d\n",i,j,cnt[i][j]);

     //}

     for(i=;i<=n;i++){

         for(j=;j<=m;j++){

             if(cnt[i][j]!=cnt[][]){

                 printf("NO\n");

                 return ;

             }

         }

     }

     printf("YES\n");

     return ;

 }