Vertical calculation method of division: every digit of dividend is divided from the high position, and the quotient obtained from each calculation is retained, and the next digit is added to the remainder for operation. After all the digits of the dividend are calculated in this order, the obtained quotients are combined in order, and the remainder is the result of the last operation.

The vertical calculation method of multiplication: multiply the number on each bit of the second factor by the first factor, from one digit to one digit. Then, add up the products.

Multiplication and division algorithm

1, multi-digit division law integer division starts from high order. Divide by a few and see how many there are.

This is not enough to see the next one, except which one is for business.

The remainder is less than the divisor, which is not enough for quotient one zero.

2. Quotient is constant. Dividend and divisor are multiplied at the same time, and the multiplication factors should be the same.

Divider and divisor are divided by the same number.

In addition to the multiplication and division of 0, the invariance of quotient should be clearly remembered.