View Compilation Error

0_0_16087342_3577.cpp: In function 'int main()':
0_0_16087342_3577.cpp:5:21: error: 'M' was not declared in this scope
   while(scanf("%d",&M)!=EOF)
                     ^
0_0_16087342_3577.cpp:8:21: error: 'a' was not declared in this scope
      if(A>B){temp=A;a=B;B=temp;}
                     ^