字符串

#include <stdio.h>
#include <string.h>
int main()
{
    char    str1[]="abcdefghijklmnopqretuvwxyz";
    char    str2[]="iiiii";
    
    char    str3[]="abcdefghijklmnopqretuvwxyz";
    char    str4[]="oooooooo";
    int count1,count2;

        count1=0;
    while (str1[count1])
        count1++;
        printf("
%d
",count1);

    count2=strlen(str2);
        printf("%d
",count2);

    if(sizeof (str2)<=sizeof(str1))
    strcpy(str1,str2);
    printf("%s",str2);
        printf("

%s",str1);
    
    count2=0;
    count1=8;
    while (str3[count2])    
    str4[count1++]=str3[count2++];

        printf("




%s",str4);
    
    system("pause");


}

#include <stdio.h>
int main()
{
    char a[]="To be or not to be";
    char b[]=",that is a question";
    int count =0;
    while (a[count]!='')
        count++;
    printf("
 The length of the string "%s" is %d characters.
",a,count);
    count=0;
    while (b[count])
        count++;
    printf("
 The length of the string "%s" is %d characters.",b,count);

system("pause");    
return 0;

}

#include <stdio.h>
int main()
{
    char a[44]="To be or not to be";
    char b[]=",that is a question";
    int count1 =0;
    int count2 =0;
    while (a[count1]!='')
        count1++;
    printf("
 The length of the string "%s" is %d characters.
",a,count1);

    while (b[count2])
        count2++;

    printf("
 The length of the string "%s" is %d characters.",b,count2);
    

    if(sizeof a<count1+count2+1)
        printf("
 You can't do it ");

    else {
    
        count2=0;
        while (b[count2])
            a[count1++]=b[count2++];
        a[count1]='';
        printf("

%s",a);   
    }

    system("pause");    
    return 0;

}//连接字符串

#include <stdio.h>
int main()
{    
    int i;

    char str[][40]={
    
        "To be or not to be",//18
        "that is a problem."//19
    };//二维数组声明

    int count[]={0,0};

    for(i=0;i<2;i++)
        while((str[i][count[i]])!=0)//!=0我加的
            count[i]++;


    /*   
    count[0]=0;
    i=0
    str[0][0]!=0
    count[0]++
    str[0][1]!=0
    count[0]++
    ...
    ...
    str[0][18]!=0
    count[0]==18
    str[0][19]=0
    跳出while 


    count[1]=0;
    i=1;
    str[1][count[1]]!=0
    count[1]++
    ...
    ...

    str[1][18]!=0
    count[1]++
    此时=19
    跳出while
    
    */

    if(sizeof str[0]<count[0]+count[1]+1)//count[0],count[1]分别为字符个数(不包括)
        printf("
 You can't put a quart into a pin pot.");
    else 
    {
        count[1]=0;//正好接到后面
        while (( str[0][count[0]++]=str[1][count[1]++] ));
        printf("
%s
",str[0]);
    }

    system("pause");    
    return 0;

}//字符串数组

#include <stdio.h>
#include <string.h>
#define S 40
int main(void)
{
    char str1[S]="abcdefghijklmnopqretuvwxyz";
    char str2[S]="iiiiiiiiiiii";
    char str3[]="The quick brown fox";
    char str4[]="The quick black fox";

    if (S>strlen(str1)+strlen(str2))
        printf("
 %s 
",strcat(str1,str2));
    
    else 
        printf("
 You can't put a quart int a pint pot");
    



    if(strcmp(str3,str4)>0)
        printf("str3>str4");
    else 
        printf("str3<str4");


    system("pause");
    return 0;
    

    
}

#include <stdio.h>
#include <string.h>
#define S 40
int main(void)
{

    char str1[]="The quick brown fox";
    char str2[]="The quick black fox";
    char str3[]="The quick";

    if(strstr(str2,str3)==NULL)
        printf("shibai");
    else 
        printf("zhaodaole");
    system("pause");
    return 0;
    

    
}

#include <stdio.h>
#include <string.h>
#include <ctype.h>
#define S 20
int main(void)
{

    char  buffer[S];
    int i=0;
    int num_letters =0;
    int num_digits =0;

    printf("
 Enter an interesting string of less than 80 ...");

    gets(buffer);

    if(gets(buffer)==NULL)
    {
    printf("Error input");
    return 1;
    }//检验gets函数是否出错(一般读取文件可能错)，一般键盘输入不会出错(gets函数可以接受所有的字符包括空格 不像scanf那样遇见空格视为结束)


    while (buffer[i]!='')
    {
        if(isalpha(buffer[i]))
            num_letters++;
        if(isdigit(buffer[i++]))
            num_digits++;
    }
    printf("
zhimu:%d
shuzhi:%d
",num_letters,num_digits);
    
    system("pause");
    return 0;
    

    
}