View Compilation Error

0_0_19940733_1101.cpp: In function 'int main()':
0_0_19940733_1101.cpp:10:16: error: 'n' was not declared in this scope
     while(cin>>n>>m)  
                ^
0_0_19940733_1101.cpp:10:19: error: 'm' was not declared in this scope
     while(cin>>n>>m)  
                   ^