C语言学习笔记之字符串间的那些事

#include <stdio.h>

int main(void) {

    printf("%s, %p, %c\n", "Who", "you", *"are");

    return 0;
}

#inclue<stdio.h>
#include<string.h>
int main()
{
	char str[]="hello world";
	int len=strlen(str);
	printf("%d",len);//len=11
}

#include<stdio.h>
#include<string.h> 
int main()
{
	char str[]="hello world";
	char s[]="hello earth";
	strcpy(str,s);
	printf("%s",str);//打印结果是hello earth
} 

#include<stdio.h>
#include<string.h> 
int main()
{
	char str[]="hello world";
	char s[]="hello earth";
	strncpy(str,s,8);
	printf("%s",str);
} 

#include<stdio.h>
#include<string.h> 
int main()
{
	char str[100]="hello world";
	char s[]="hello";
	strcat(str,s);
	printf("%s",str);
} 

#include<stdio.h>
#include<string.h> 
int main()
{
	char str[100]="hello world";
	char s[]="hello";
	strncat(str,s,4);
	printf("%s",str);
} 

#include<stdio.h>
#include<string.h> 
int main()
{
	char str1[]="hello world";
	char str2[]="hello world";
	int ret;
	ret=strcmp(str1,str2);
	printf("%d",ret);//ret==0
} 

#include<stdio.h>
#include<string.h> 
int main()
{
	char s1[]="hello world";
	char s2[]="hello earth";
	int ret;
	ret=strncmp(s1,s2,5);
	if(ret>0)
		printf("s1的前五个字符大于s2的前五个字符\n"); 
	else if(ret<0)
		printf("s1的前五个字符小于s2的前五个字符\n"); 
	else
		printf("s1的前五个字符等于s2的前五个字符\n"); 
} 

#include<stdio.h>
#include<string.h>
 
int main()
{
	char a[100][100],birth[100][100],s[100];
	int n,i,j;scanf("%d",&n);
	gets(s);
	for(i=0;i<n;i++)
	{
		gets(a[i]);
		strncpy(birth[i],a[i]+6,8);
	}
	for(i=0;i<n;i++)
	{
		for(j=i+1;j<n;j++)
		{
			if(strcmp(a[j],a[i])<0)
			{
				strcpy(s,a[j]);
				strcpy(a[j],a[i]);
				strcpy(a[i],s);
			}
		}
	}
	for(i=0;i<n;i++)
	{
		printf("%s\n",a[i]);
	}
 }