C&C++常用小函数 代码

格式化输入输出文件

#include "stdafx.h"
#include <stdlib.h>
#include "string.h"
#include  "stdio.h"
int   main() 
{     
 FILE *fp;
 int number[3];
 int score[3];
 int i = 0;
 int rece_Number = 0;
 if((fp = fopen("test.txt","r")) == NULL)
 {
  fprintf(stderr,"Error opening file!/n");
 }
 for(i =0;i<3;i++)
 {
        fscanf(fp,"%d %d",&number[i],&score[i]);//学号与成绩用空格
 }
 printf("Please input number:/n");
 scanf("%d",&rece_Number);
 for(i = 0;i<3;i++)
 {
        if(rece_Number == number[i])
  break;
 }
    printf("The Number's score is %d/n",score[i]);
 fclose(fp);
 return 0;
} 

统计字符串中最长的重复字符串

#include "stdafx.h"
#include "string.h"
#include "malloc.h"

int main()
{
 int i,j,k,t;
 int max = 0;
 char *p = NULL;
 char str[42] = "2xtuaojy5678zuaojy908puaojy417uaojy356";
 char temp[8];
    char result[8];
 memset(result,0,8);
 p = str;
    for(i=0;i <42;i++) 
    {
        for(j=i+1;j <42;j++) 
        { 
            if(*(p+i)== *(p+j)) 
            { 
    t = i;
    k = 0;
       memset(temp,0,8);
    //只要找到了相同的首字符，就开始比较直到没有相同的字符，记录当前字符串，看是否是最长的
                while(*(p+t)== *(p+j))
    {
     temp[k] = *(p+t);//不断比较后续的字符
     t++;
     j++;
     k++;
    }
    if(k > max)//将最长的字符串赋值给result
    {
     max = strlen(temp);
                   strcpy(result,temp);
    }
      
            } 
  
        }
 
    }
    //打印出结果在上述字符串中最长的是 "zuaojy"
 printf("重复字符串最长的是 %s,长度为 %d /n",result,max);
 return 0;
}

通过递归求字符串中出现的相同字符次数

int count_times(char ch,const char* str)
{
 int count = 0;
 if(*str == '/0')
 {
  count = 0;
 }
 else
 {
 if((*str)==ch)
 {
        count = 1+count_times(ch,str+1);
 }
 else
 {
        count = count_times(ch,str+1);
 }
 }
 return count;
}