View Compilation Error

0_0_13640228_13249.cpp: In function 'int main()':
0_0_13640228_13249.cpp:21:6: error: 'sum' was not declared in this scope
      sum+=j;break;
      ^
0_0_13640228_13249.cpp:23:23: error: 'sum' was not declared in this scope
         printf("%d\n",sum);
                       ^