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Preface

C Language sentences

The branch family of love choice

Omnipotent brother if

  A little brother who has found another way switch

Preface

Starting today , I will continue to share with you what I have learned C History , What I'm sharing with you today is the branch statement .

C Language sentences

C Sentences can be divided into the following five categories ： 1. Expression statement

                                        2. Function call statements

                                        3. Control statement

                                        4. Compound statement

                                        5. Empty statement

What I want to share today is ： Control statement

So what is a control statement ？

In short, it is the process of controlling program execution , stay C There are three families in language .

  Today, let's introduce ： The branch family of love choice , In the following, we will introduce the circulation family of one tendon and the steering family of turning .

The branch family of love choice

There are two members in this family , Omnipotent brother if And the little brother who found another way switch. The members of this family have a common characteristic is love " choice ", Come on, let's go into this interesting family ！

Omnipotent brother if

if Big brother's cognition ： expression （" really " Just get up ," false " Just bye ）

0 Said the false , Not 0 Said really .

Illustrate with examples ：

#define  _CRT_SECURE_NO_WARNINGS

#include<stdio.h>
int main()
{
	int a = 0;
	printf(" Selectivity C Language attitude :\n");
	scanf("%d", &a);
	if (0 != a)
	{
		printf(" Study hard C Language \n");
	}
	else
	{
		printf(" Don't study hard C Language \n");
	}
	return 0;
}

Print ：

  know if Brother's attention ：1 if I love the one closest to him else( Match ).

                                   2 if To execute multiple statements later, use {}.

  A little brother who has found another way switch

  about switch We should pay special attention to , His judgment condition is Shaping expression .

Illustrate with examples ：

#include<stdio.h>

int main()
{
	int day = 0;
	scanf("%d", &day);
	switch (day)
	{
		case 1:
			printf(" Monday \n");
			break;
		case 2:
			printf(" Tuesday \n");
			break;
		case 3:
			printf(" Wednesday \n");
			break;
		case 4:
			printf(" Thursday \n");
			break;
		case 5:
			printf(" Friday \n");
			break;
		case 6:
			printf(" Saturday \n");
			break;
		case 7:
			printf(" Sunday \n");
			break;
		default:
			printf(" Wrong choice \n");
			break;
	}
	return 0;
}

Print :

In order to change

1. Input 1-5, The output is “weekday”;

2. Input 6-7, Output “weekend”

How can we write ：

#include <stdio.h>
//switch Code demonstration 
int main()
{
    int day = 0;
    scanf("%d", &day);
    switch (day)
    {
        case 1:
        case 2:
        case 3:
        case 4:
        case 5:
                 printf("weekday\n");
                 break;
        case 6:
        case 7:
                  printf("weekend\n");
                  break;
   }
   return 0;
}

switch Summary of ：1 It means to jump out of this cycle break.

                          2 When switch The value of the expression is the same as all case If the values of the tags do not match, the statement will be skipped .

                          3  default（/dɪ'fɔːlt/） Can appear in switch Anywhere in , And only 1 strip , do Use is when the value in the expression and csae When it doesn't match, start from default The statement following the clause will execute .

                          4 We usually work in every case Add a... After each statement break Develop good programming habits .