What is the difference between a++ and ++a?

The difference is: the timing of incrementing the value of variable "a" is different; "a" and "a" are both auto-increment operators; "a" takes the value first and then increments it "1"; "a" is first incremented by "1" and then taken.

a and a are both auto-increment operators. The difference is that the timing of incrementing the value of variable a is different. a is taken first and then incremented. a is auto-incremented first and then taken.

Example

For example: Suppose x=3, y=4;

(1) (x) (x)=8

Explanation: For the first (x), because x takes the value first and then increments, the value obtained by (x) is 3, and then x increments, at this time x=4; for the first Two (x), because x is incremented first and then takes the value, so the value obtained by (x) is 5. At this time, x=5, so the result is 8.

(2) (x )/3 (--y)*2-(x--)%6 (y )*3-(y--)

1 6-4 9-4=8

Explanation: First (x) takes the value 3, then x=4; then (--y) takes the value 3, at this time y=3; Then (x--) takes the value 4, then x=3; then (y) takes the value 3, then y=4; finally (y--) takes the value 4, then y=3;

Note :() can increase the arithmetic priority, so the expression in the brackets is calculated first, but the value of x is x, and then x is incremented.

Key points: The operation priority is very high

Interview question:

int  i = 10
i  =  i++ ;

At this time, what is the value of i?

Answer: The value of input i is 10

Analysis: First, the value of i is 10, then i is incremented, at this time, i=11, and finally the value is assigned. So the final output value of i is 10.

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