foo.cc: In function 'int main()':
foo.cc:18:5: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
     for(int i=1;i<=n;++i)
     ^~~
foo.cc:20:9: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
         cout<<res;
         ^~~~

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