View Compilation Error

0_0_22946584_15558.cpp: In function 'int main()':
0_0_22946584_15558.cpp:21:17: error: 'i' was not declared in this scope
             for(i=1;i<=v;i++)  
                 ^
0_0_22946584_15558.cpp:23:17: error: 'i' was not declared in this scope
             for(i = 0;i<num;i++)  
                 ^
0_0_22946584_15558.cpp:30:17: error: 'i' was not declared in this scope
             for(i=v;i>=0;i--)  
                 ^