View Compilation Error

0_0_33226621_26850.cpp: In function 'int main()':
0_0_33226621_26850.cpp:42:28: error: 'u' was not declared in this scope
             scanf("%d%d", &u, &v);
                            ^
0_0_33226621_26850.cpp:42:32: error: 'v' was not declared in this scope
             scanf("%d%d", &u, &v);
                                ^