View Compilation Error

0_0_21292772_2148.cpp: In function 'int main()':
0_0_21292772_2148.cpp:4:13: error: 'a' was not declared in this scope
  while(cin>>a>>b){
             ^
0_0_21292772_2148.cpp:4:16: error: 'b' was not declared in this scope
  while(cin>>a>>b){
                ^