View Compilation Error

0_0_18855781_8102.cpp: In function 'int main()':
0_0_18855781_8102.cpp:12:27: error: 'n' was not declared in this scope
     while( ~scanf("%d%d",&n,&m))
                           ^
0_0_18855781_8102.cpp:12:30: error: 'm' was not declared in this scope
     while( ~scanf("%d%d",&n,&m))
                              ^