View Compilation Error

0_0_27220036_32113.cpp: In function 'int main()':
0_0_27220036_32113.cpp:4:26: error: 'a' was not declared in this scope
    while(~scanf("%d %d",&a,&b))
                          ^
0_0_27220036_32113.cpp:4:29: error: 'b' was not declared in this scope
    while(~scanf("%d %d",&a,&b))
                             ^