---
title: C lang
tags: C C++
abbrlink: 12462
date: 2025-01-15 20:41:26
---

### c lang在windows下的开发（VS code）
[WinLibs - GCC+MinGW-w64 compiler for Windows](https://winlibs.com/#download-release)下载你需要的版本
解压到`D:\ProgramModule`，并将 `bin\`加入环境变量`PATH`
打开新的`Terminal`输入`gcc -v`，查看`gcc`是否安装成功
在`VS code` 的插件管理下载`Code Runner`、`C\C++`这两个插件
在`*.c`源文件的内容区，右键点击`Run Code` ，即可运行成功
![](/img/language/c-env-conf.png)

### 数据类型
- 整数类型
  ```c
    short a = 12;
    int b = 100;
    long c = 1000L;
    long long d = 1000000LL;
    unsigned int e = 10;
    printf("a: %hd\n",a);
    printf("b: %d\n",b);
    printf("c: %ld\n",c);
    printf("d: %lld\n",d);
    printf("e: %u\n",e);
    printf("f: %.3f\n",f);
    ```
- 小数类型
  ```c
    float f = 3.14F;
    printf("f: %.3f\n",f);
    double g = 5.65;
    printf("g: %.2lf\n",g);
    ```
- 字符类型
  ```c
    char h = 'x';
    printf("x: %c\n",x);
    ```
### 类型转换
- 隐式转换
- 强制转换
  ```c
    int b = 23;
    short c = (short) b;
    ```
### 数组
```c
#include <stdio.h>

int main(){
    int arr [10] = {2,3,4,5,6,7,8,9,10,11};
    arr[0] = 1525;
    *(arr+1) = 25;
    int len = sizeof(arr)/sizeof(arr[0]);
    void printArr(int arr[], int len){
        for (int i = 0; i < len;i++){
            printf("%d\t",arr[i]);
        }
    }
    printArr(arr,len);
    return 0;
}
```
### 指针
```c
    // swap the value of a and b
    void swap(int* x, int* y){
        int temp = *x;
        *x = *y;
        *y = temp;

    }
    int a = 5;
    int b = 10;
    swap(&a, &b);
    printf("a = %d b = %d\n", a, b);
```