What is the difference between while loop and do while loop?

The difference is: 1. The while loop determines the condition first and then executes the loop body, while the do-while loop executes the loop body first and then determines the condition; 2. The while loop determines the loop condition first. If the condition is met, Then execute the code in the loop body, and then judge the condition again, and loop like this until the condition is not met. Jump out of the loop, while the do-while loop first executes the code in the loop body, and then determines whether the loop condition is met. If the condition is met, , then continue to execute the code in the loop body, and loop like this until the loop is jumped out when the condition is not met.

while loop and do-while loop are two common loop structures. The difference between them lies in the timing of judging loop conditions.

The while loop first determines the loop condition. If the condition is met, the code in the loop body is executed, and then the condition is determined again. This loop continues until the condition is not met and the loop is exited. In other words, the while loop will perform conditional judgment before executing the loop body. If the condition is not met at the beginning, the loop body will not be executed.

The do-while loop first executes the code in the loop body, and then determines whether the loop condition is met. If the condition is met, continue to execute the code in the loop body, and so on until the condition is not met. cycle. In other words, a do-while loop will execute the loop body at least once, even if the condition is not met initially.

In summary, while loops first determine the condition and then execute the loop body, while do-while loops execute the loop body first and then determine the conditions. Depending on specific needs, choosing an appropriate loop structure can better control the flow of the program.

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