int main
{
int A,B,C;
int C = 0;
 scanf("%d %d", &A &B);
 printf("入力値 A=%d,B=%d",A,B);

 if(0 < A < 10 && 0 < B < 10){
     C = A * B;
     printf("%d",C);
 }
 else{
     C = -1;
     printf("%d",C);
 }
 return 0;
}