Judgment and loop statement Structure

I. Judgment statement:

1. If statement:

A. If (){

// Execute the statement;

}

B. If (){

// Execute the statement;

} Else {

// Execute the statement;

}

C. If (){

// Execute the statement;

} Else if {

// Execute the statement;

}

......

Else {

// Execute the statement;

}

2. Switch statement:

Switch (expression ){

Case constant expression 1: Statement 1;

Case constant expression 2: Statement 2;

......

Default: statement;

}

Ii. Loop statement:

1. For Loop statement:

For (Initial Value of the cyclic variable; cyclic condition; value-added value of the cyclic variable ){

Statement;

}

2. While loop:

While (condition ){

// Loop body;

}

3. Do while loop:

Do {

// Loop body;

} While (condition)

Iii. Differences between loop statements:

1. For and while loops:

For loops are mostly used to know the number of loops;

While loops are mostly used to determine the number of loops without knowing the number of loops;

2. Differences between a while loop and a do while loop:

Do while first executes the loop body, and then judges the condition. If the condition is met, continue the execution. If the condition is not met, exit the loop;

When a while loop first determines the condition, it executes the loop body and does not exit;