C高级【day4】

思维导图：

写一个函数，获取用户的uid和gid并使用变量接收：

#!/bin/bash

function get_uid
{
	my_uid=`id -u`
	my_gid=`id -g`
}

get_uid
echo "当前用户的UID：$my_uid"
echo "当前用户的GID：$my_gid"

整理冒泡排序、选择排序和快速排序的代码

快速排序：

#include<myhead.h>

//一次排序函数
int one_sort(int arr[], int low, int high){
	int key=arr[low];
	while(low < high){
		//右边循环比较
		while(low < high && key <= arr[high]){
			high--;
		}
		arr[low] = arr[high];
		//左边循环比较
		while(low < high && key >= arr[low]){
			low++;
		}
		arr[high] = arr[low];
	}
	arr[low] = key;
	return low;
}

void quick_sort(int arr[], int low, int high){
	if(low < high){
		int mid = one_sort(arr, low, high);
		//中间值右侧递归排序
		quick_sort(arr, low, mid-1);
		//中间值左侧递归排序
		quick_sort(arr, mid+1, high);
	}
}

int main(int argc, const char *argv[])
{
	int arr[]={1,4,5,7,3,12,99,45,2,77};
	int len = sizeof(arr)/sizeof(arr[0]);
	quick_sort(arr, 0, len-1);
	
	for(int i=0; i < len; i++){
		printf("%d\t", arr[i]);
	}
	putchar(10);
	return 0;
}

冒泡排序：

#include<myhead.h>

void bub_sort(int arr[], int len){
	int temp = 0;
	int count = 0;
	for( int i = 0; i < len/2; i++){
		for( int j = i+1;  j < len-i; j++){
			if( arr[i] > arr[j]){
				temp = arr[i];
				arr[i] = arr[j];
				arr[j] = temp;
			}
		}
	}
}

int main(int argc, const char *argv[])
{
	int arr[] = {12, 26, 24, 8, 16, 1, 99};
	int len = sizeof(arr)/sizeof(arr[0]);
	bub_sort(arr, len);
	
	for(int i=0; i < len; i++){
		printf("%d\t", arr[i]);
	}
	putchar(10);

	return 0;

简单选择排序：

#include<myhead.h>

void select_sort(int arr[], int len){
	int temp = 0;
	for( int i = 0; i < len-1; i++){
		int min=i;
		for( int j = i+1; j < len; j++){
			if(arr[min] > arr[j]){
				min = j;
			}
		}
		if(min != i){
			temp = arr[i];
			arr[i] = arr[min];
			arr[min] = temp;
		}
	}
}

int main(int argc, const char *argv[])
{
	int arr[] = { 12, 15, 99, 26, 28, 8, 24};
	int len = sizeof(arr)/sizeof(arr[0]);
	select_sort(arr, len);
	
	for(int i=0; i < len; i++){
		printf("%d\t", arr[i]);
	}
	putchar(10);

	return 0;
}