foo.cc: In function 'int M(int, int)':
foo.cc:8:29: warning: value computed is not used [-Wunused-value]
  if(num%2!=0){M(alpha,num-1)*alpha;}
               ~~~~~~~~~~~~~~^~~~~~
foo.cc:11:10: warning: 'c' may be used uninitialized in this function [-Wmaybe-uninitialized]
   return c;
          ^
foo.cc: In function 'int main()':
foo.cc:11:10: warning: 'c' may be used uninitialized in this function [-Wmaybe-uninitialized]
   return c;
          ^
foo.cc:7:8: note: 'c' was declared here
   long c;
        ^

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