View Compilation Error

0_0_28174382_4807.cpp: In function 'int main()':
0_0_28174382_4807.cpp:15:8: error: 'sum' was not declared in this scope
     if(sum>=1)
        ^
0_0_28174382_4807.cpp:17:5: error: 'sum' was not declared in this scope
     sum++;
     ^
0_0_28174382_4807.cpp:21:6: error: 'sum' was not declared in this scope
   if(sum==0)
      ^