View Compilation Error

0_0_28602938_29611.cpp: In function 'int main()':
0_0_28602938_29611.cpp:12:23: error: 'n' was not declared in this scope
  while(~scanf("%d%d",&n,&m)){
                       ^
0_0_28602938_29611.cpp:12:26: error: 'm' was not declared in this scope
  while(~scanf("%d%d",&n,&m)){
                          ^