foo.cc: In function 'int main()':
foo.cc:7:18: warning: comparison of integer expressions of different signedness: 'int' and 'unsigned int' [-Wsign-compare]
    7 |     for(int i=1;i<=2*a;i++)
      |                 ~^~~~~
foo.cc:9:5: warning: this 'while' clause does not guard... [-Wmisleading-indentation]
    9 |     while(a!=0)
      |     ^~~~~
foo.cc:11:9: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'while'
   11 |         cout<<"YES";
      |         ^~~~
foo.cc:5:22: warning: unused variable 'cnt' [-Wunused-variable]
    5 |     unsigned int a,d,cnt=0;
      |                      ^~~

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