急寻c ++八进制整数加减乘运算

//八进制字符串转十进制整型
int _8210( char *num )
{
int iBase = 8 ;
int iTemp = 1 ;
int iii = 0 ;

for ( int i = strlen( num ) - 1 ; i >= 0 ; i -- )
{
if ( i < (int)strlen( num ) - 1 )
iTemp *= iBase ;
iii += ( num[i] - 48 ) * iTemp ;
}
return iii ;
}

//加发
int _Jia8( char *num1 ,char *num2 )
{
return _8210(num1) + _8210(num2) ;
}

//减法
int _Jian8( char *num1 ,char *num2 )
{
return _8210(num1) - _8210(num2) ;
}

//乘法
int _Cheng8( char *num1 ,char *num2 )
{
return _8210(num1) - _8210(num2) ;
}

//除法
int _Chu8( char *num1 ,char *num2 )
{
//判断除零错误
if ( _8210(num2) == 0 )
return 0 ; //或其他的值
return _8210(num1) / _8210(num2) ;
}

int main()
{
char n1[] = "107" ;
char n2[] = "17" ;
printf( "%d"