View Compilation Error

0_0_33975676_18127.cpp: In function 'int main()':
0_0_33975676_18127.cpp:14:3: error: 'll' was not declared in this scope
   ll sum = 0 ;
   ^
0_0_33975676_18127.cpp:15:3: error: 'sum' was not declared in this scope
   sum += k-1;
   ^