func_code_string: #include <bits/stdc++.h>   using namespace std;   bool vis[2][100005];   char c[2][100005];   int main() {     queue<pair<int, pair<int, int> > > q;     bool flag = 0;     int n, k;     cin >> n >> k;     scanf( %s%s , c[0], c[1]);     q.push(make_pair(0, make_pair(0, 0)));     while (!q.empty()) {       int x = q.front().first, y = q.front().second.first,           de = q.front().second.second;       q.pop();       if (y >= n) {         flag = 1;         break;       }       if (vis[x][y] || de > y) continue;       vis[x][y] = 1;       if (y - 1 >= 0 && c[x][y - 1] !=  X  && y - 1 >= de + 1 && !vis[x][y - 1]) {         q.push(make_pair(x, make_pair(y - 1, de + 1)));       }       if (y + 1 >= n || (c[x][y + 1] !=  X  && !vis[x][y + 1])) {         q.push(make_pair(x, make_pair(y + 1, de + 1)));       }       if (y + k >= n || (c[x ^ 1][y + k] !=  X  && !vis[x ^ 1][y + k])) {         q.push(make_pair(x ^ 1, make_pair(y + k, de + 1)));       }     }     if (flag)       cout <<  YES ;     else       cout <<  NO ;   }   