View Compilation Error

0_0_39417701_20611.cpp: In function 'int main()':
0_0_39417701_20611.cpp:7:14: error: 'a' was not declared in this scope
    7 |  while(cin>> a >>b) cout<< a+b<<endl;
      |              ^
0_0_39417701_20611.cpp:7:18: error: 'b' was not declared in this scope
    7 |  while(cin>> a >>b) cout<< a+b<<endl;
      |                  ^