View Compilation Error

0_0_18706500_3000.cpp: In function 'int main()':
0_0_18706500_3000.cpp:63:19: error: too few arguments to function 'long long unsigned int gcd(long long unsigned int, long long unsigned int)'
         if(gcd(n%m)==1)
                   ^
0_0_18706500_3000.cpp:28:20: note: declared here
 unsigned long long gcd(unsigned long long a,unsigned long long b)
                    ^