View Compilation Error

0_0_17600212_14600.cpp: In function 'int main()':
0_0_17600212_14600.cpp:62:20: error: too few arguments to function 'long long int haha(long long int, long long int)'
    cout << haha(sum) <<endl;
                    ^
0_0_17600212_14600.cpp:13:4: note: declared here
 ll haha(ll n,ll sum){
    ^