View Compilation Error

0_0_26604432_15939.cpp: In function 'int main()':
0_0_26604432_15939.cpp:46:17: error: 'sum' was not declared in this scope
                 sum += x;
                 ^
0_0_26604432_15939.cpp:55:30: error: 'sum' was not declared in this scope
         for (int i = 1; i <= sum; i++) {
                              ^