字符串输入的拓展

 

 

 

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
const size_t BUFFER_LEN =128;
const size_t NUM_P =3;
char buffer[128];
char *pS[3]={NULL};
char *pbuffer =buffer ;
int i;
int main()
{
    printf("\n You can enter up to %u message each up to %u ge ",NUM_P,BUFFER_LEN-1);
    
    for (i=0;i<NUM_P;i++)
    {
        pbuffer=buffer ;
        printf("\n  Enter %s message ",i>0?"another":"a");
        
        while ((pbuffer-buffer<BUFFER_LEN-1)&&(*(pbuffer++)=getchar())!='\n');
        
        if((pbuffer-buffer)<2)
            break;
        
        if((pbuffer-buffer)==BUFFER_LEN&&*(pbuffer-1)!='\n')
        {
            printf("String too long ");
            i--;
            continue;
            
        }
        
        
        
        *(pbuffer-1)='\0';
        
        pS[i]=(char*)malloc(pbuffer-buffer);
        
        if(pS[i]==NULL)
        {
            printf("\n OUT of memory ");
            return 1;            
        }
        
        strcpy(pS[i],buffer);    
        
    }
    
    printf("\n In reverse order .the strings you entered are :\n");
    
    while (--i >= 0)
    {
        printf("\n%s",pS[i]);
        free(pS[i]);
        pS[i]=NULL;
    }
    
    system("pause");
    return 0;
    
    
    
    
}

 

 

 

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
const size_t BUFFER_LEN =10;
const size_t NUM_P =3;
char buffer[10];
char *pS[3]={NULL};
char *pbuffer =buffer ;
int i;



int main()
{
    printf("\n You can enter up to %u message each up to %u ge ",NUM_P,BUFFER_LEN-1);
    
    for (i=0;i<NUM_P;i++)//遍历指针数组
    {
        pbuffer=buffer ;//把数组首地址给指针
        printf("\n  Enter %s message ",i>0?"another":"a");
        
        while ((pbuffer-buffer<BUFFER_LEN-1)&&(*(pbuffer++)=getchar())!='\n');
        /*
        pbuffer-buffer=0    1     pbuffer+1 
        
        pbuffer-buffer=1     2     pbuffer+1
        
        
        pbuffer-buffer=BUFFER_LEN-2     BUFFER_LEN-1   pbuffer+1

            pbuffer-buffer=BUFFER_LEN-1   跳出循环  
        
        
        */
        
        
        if((pbuffer-buffer)<2)
            /*
        检查你是否是直接按下回车,那样话，pbuffer-buffer=1 仅仅输入了一个'\n'
        */
        {
            printf("zhiyou huiche yayayayaayaya");
            break;
        }
        
        
        
        if((pbuffer-buffer)==BUFFER_LEN&&*(pbuffer-1)!='\n')
        {
            printf("String too long ");
            i--;
            continue;
            
        }
        
        
        
        *(pbuffer-1)='\0';
        
        pS[i]=(char*)malloc(pbuffer-buffer);//分配内存，大小为当前pbuffer指向地址-buffer地址
        
        if(pS[i]==NULL)
        {
            printf("\n OUT of memory ");
            return 1;            
        }
        
        strcpy(pS[i],buffer);    //把字符串复制到新内存中
        
    }
    
    printf("\n In reverse order .the strings you entered are :\n");
    
    while (--i >= 0)
    {
        printf("\n%s",pS[i]);
        free(pS[i]);
        pS[i]=NULL;
    }
    
    system("pause");
    return 0;
    
    
    
    
}

 

 

 

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
const size_t BUFFER_LEN =12;
const size_t NUM_P =3;
char buffer[12];
char *pS[3]={NULL};
char *pbuffer =buffer ;
int i;
int main()
{
    printf("\n You can enter up to %u message each up to %u ge ",NUM_P,BUFFER_LEN-1);
    
    for (i=0;i<NUM_P;i++)
    {
        pbuffer=buffer ;
        printf("\n  Enter %s message ",i>0?"another":"a");
        
        printf("\n@pbuffer-buffer%d\n",pbuffer-buffer);
        printf("\n@@pbuffer%d\n",pbuffer);
        printf("\n@@@pbuffer%s\n",pbuffer);//可以打印，打印的是上一次输入的字符串
    
        while ((pbuffer-buffer<BUFFER_LEN-1)&&(*(pbuffer++)=getchar())!='\n')//在不按\n时候才自加，换句话讲，'\n'不会计数
        {
        printf("\n>pbuffer-buffer%d\n",pbuffer-buffer);
        printf("\n>>pbuffer%d\n",pbuffer);
        printf("\n>>>pbuffer%s\n",pbuffer);//打印不出，大概是因为没有内存吧？？

        };
        
        if((pbuffer-buffer)<2)
            break;
        
        if((pbuffer-buffer-BUFFER_LEN)&&*(pbuffer-1)!='\n')
        {
            printf("String too long ");
            i--;
            continue;
            
        }
        
        
        
      
        
        pS[i]=(char*)malloc(pbuffer-buffer);
        
        if(pS[i]==NULL)
        {
            printf("\n OUT of memory ");
            return 1;            
        }
        
        strcpy(pS[i],buffer);    
        
    }
    
    printf("\n In reverse order .the strings you entered are :\n");
    
    while (--i >= 0)
    {
        printf("\n%s",pS[i]);
        free(pS[i]);
        pS[i]=NULL;
    }
    
    system("pause");
    return 0;
    
    
    
    
}

/*

解决一个问题最好的办法是，提出几个假设，然后设计实验验证他，应用他
书写为了更好思考，可以整理思路

*************
最大的恐惧正是恐惧本身。
**************


*/