/in/foo.cc: In function 'int main()':
/in/foo.cc:6:17: warning: unused variable 'a' [-Wunused-variable]
     long long k,a=0,b=1,m=0;  
                 ^
/in/foo.cc:6:21: warning: unused variable 'b' [-Wunused-variable]
     long long k,a=0,b=1,m=0;  
                     ^
/in/foo.cc:6:25: warning: unused variable 'm' [-Wunused-variable]
     long long k,a=0,b=1,m=0;  
                         ^