View Compilation Error

0_0_13286057_7970.cpp: In function 'int main()':
0_0_13286057_7970.cpp:37:30: error: 'flag' was not declared in this scope
             if(n[i].a>n[i].b)flag=2;
                              ^
0_0_13286057_7970.cpp:38:36: error: 'flag' was not declared in this scope
             else if(n[i].a==n[i].b)flag=1;
                                    ^
0_0_13286057_7970.cpp:39:18: error: 'flag' was not declared in this scope
             else flag=0;
                  ^
0_0_13286057_7970.cpp:45:16: error: 'flag' was not declared in this scope
             if(flag==2)printf(">");
                ^