View Compilation Error

0_0_39536503_9198.cpp: In function 'int main()':
0_0_39536503_9198.cpp:68:51: error: 'k' was not declared in this scope
   68 |                 for(int i = 2;i <= n;i ++) if(vis[k] == 0) g = gcd(g,a[i]);
      |                                                   ^