/in/foo.c: In function 'hw':
/in/foo.c:32:15: warning: unused variable 'm' [-Wunused-variable]
     int i=0,j,m,k,sum=0;
               ^
/in/foo.c: In function 'zh':
/in/foo.c:64:15: warning: implicit declaration of function 'pow' [-Wimplicit-function-declaration]
         if(b>=pow(n,i))
               ^~~
/in/foo.c:64:15: warning: incompatible implicit declaration of built-in function 'pow'
/in/foo.c:64:15: note: include '<math.h>' or provide a declaration of 'pow'
/in/foo.c:61:11: warning: unused variable 'j' [-Wunused-variable]
     int i,j,c=0,d;
           ^