View Compilation Error

0_0_15153953_20666.cpp: In function 'int main()':
0_0_15153953_20666.cpp:6:24: error: 'A' was not declared in this scope
   while(scanf("%d %d",&A,&B)!=EOF)
                        ^
0_0_15153953_20666.cpp:6:27: error: 'B' was not declared in this scope
   while(scanf("%d %d",&A,&B)!=EOF)
                           ^