foo.cc: In function 'int DaysOfMonth(int, int)':
foo.cc:41:4: warning: this 'else' clause does not guard... [-Wmisleading-indentation]
    else
    ^~~~
foo.cc:43:5: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'else'
     break;
     ^~~~~
foo.cc: In function 'int main()':
foo.cc:63:10: warning: unused variable 'sum' [-Wunused-variable]
  int y,m,sum=0;
          ^~~
foo.cc: In function 'int DaysOfMonth(int, int)':
foo.cc:47:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^

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