View Compilation Error

0_0_15050996_10476.cpp: In function 'int main()':
0_0_15050996_10476.cpp:24:40: error: 'a' was not declared in this scope
             scanf("%lld %lld %lld",&t,&a,&b);
                                        ^
0_0_15050996_10476.cpp:24:43: error: 'b' was not declared in this scope
             scanf("%lld %lld %lld",&t,&a,&b);
                                           ^