foo.cc: In function 'int WeekdayOfTheFirstDay(int, int)':
foo.cc:57:16: warning: unused variable 'count' [-Wunused-variable]
  int a=0,i,j,c,count;
                ^~~~~
foo.cc: In function 'int main()':
foo.cc:73:8: warning: unused variable 'b' [-Wunused-variable]
  int a,b,c,i,x,y,z,sum,d,year,month;
        ^
foo.cc:73:10: warning: unused variable 'c' [-Wunused-variable]
  int a,b,c,i,x,y,z,sum,d,year,month;
          ^
foo.cc:73:12: warning: unused variable 'i' [-Wunused-variable]
  int a,b,c,i,x,y,z,sum,d,year,month;
            ^
foo.cc:73:14: warning: unused variable 'x' [-Wunused-variable]
  int a,b,c,i,x,y,z,sum,d,year,month;
              ^
foo.cc:73:16: warning: unused variable 'y' [-Wunused-variable]
  int a,b,c,i,x,y,z,sum,d,year,month;
                ^
foo.cc:73:18: warning: unused variable 'z' [-Wunused-variable]
  int a,b,c,i,x,y,z,sum,d,year,month;
                  ^
foo.cc:73:20: warning: unused variable 'sum' [-Wunused-variable]
  int a,b,c,i,x,y,z,sum,d,year,month;
                    ^~~
foo.cc:73:24: warning: unused variable 'd' [-Wunused-variable]
  int a,b,c,i,x,y,z,sum,d,year,month;
                        ^
foo.cc: In function 'int DaysOfMonth(int, int)':
foo.cc:53:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^

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