foo.cc: In function 'int main()':
foo.cc:23:9: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   23 |         for (int i =2;i<=n;i++)
      |         ^~~
foo.cc:29:17: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   29 |                 cout << cnt;
      |                 ^~~~
foo.cc:21:13: warning: unused variable 'a' [-Wunused-variable]
   21 |         int a ,b,n = 6,cnt=0;
      |             ^
foo.cc:21:16: warning: unused variable 'b' [-Wunused-variable]
   21 |         int a ,b,n = 6,cnt=0;
      |                ^

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