View Compilation Error

0_0_37169075_8996.cpp: In function 'int main()':
0_0_37169075_8996.cpp:12:4: error: 'flag' was not declared in this scope
    flag=i
    ^
0_0_37169075_8996.cpp:16:4: error: 'flag' was not declared in this scope
    flag=i;
    ^
0_0_37169075_8996.cpp:18:6: error: 'flag' was not declared in this scope
   if(flag+b<100)printf(" ");
      ^