//对于该点能到达的下一点用一条路径表示
//然后用spfa求出其最小值
//在更新最小点时判断一下他去这一个点时会不会淹死
#include<cstdio>
#include<cstring>
#include<iostream>
#include<queue>
using namespace std ;
const int inf = 0x3f3f3f3f;
const int maxn = 100010 ;
const int mod = 100010 ;
int dis[maxn*2] ;
int vis[2*maxn] ;
char str[2][maxn] ;
int n , k;
struct Edge
{
int v ;
int next ;
}edge[10*maxn] ;
int head[2*maxn] ;
int nedge ;
void addedge(int u , int v)
{
edge[nedge].v = v;
edge[nedge].next = head[u] ;
head[u] = nedge++ ;
}
void spfa(int st)
{
for(int i = 0;i <= n ;i ++)
dis[i] = dis[i+mod] = inf ;
dis[st] = 0;
vis[st] = 1;
queue<int> que;
que.push(st);
while(que.size())
{
int u = que.front();
que.pop() ;
vis[u] = 0;
for(int i = head[u] ;i != -1 ;i = edge[i].next)
{
int t = dis[u] + 1;
int v = edge[i].v ;
if(v % mod >= t && t < dis[v])
{
dis[v] = t ;
if(!vis[v])
{
que.push(v) ;
vis[v] = 1;
}
}
}
}
}
void init()
{
memset(head , -1 ,sizeof(head)) ;
nedge = 0 ;
memset(vis , 0 ,sizeof(vis)) ;
}
int main()
{
//freopen("in.txt","r",stdin) ;
while(~scanf("%d%d" ,&n , &k))
{
scanf("%s%s" ,str[0] , str[1]) ;
init() ;
for(int j = 0 ;j < 2;j++)
for(int i = 0;i < n ;i++)
{
if(str[j][i] == ‘X‘)continue ;
if(str[j][i+1] != ‘X‘)
addedge(i + j*mod, i + j*mod +1) ,addedge(i+1 + j*mod, i + j*mod) ;
int num = i+k >= n ? n: i+k ;
if(str[!j][num] != ‘X‘)
addedge(i + j*mod, num + (!j)*mod) ;
}
spfa(0) ;
if(dis[n] == inf && dis[n+mod] == inf)
puts("NO") ;
else puts("YES") ;
}
return 0;
}