/in/foo.cc: In function 'int main()':
/in/foo.cc:24:15: warning: variable 'k' set but not used [-Wunused-but-set-variable]
       int l=0,k=0;
               ^
/in/foo.cc:32:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
  for(int i=2;i<=n;i++)
  ^~~
/in/foo.cc:35:4: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for'
    cout<<n-maxn+1;
    ^~~~