如何在struct中附加元素而不覆盖 [英] How to append elements without overwriting in struct

问题描述

在这段代码中，我试图调用

In this code I'm trying to call

rrandom

来选择一个随机id和名称并将其放入buff结构中，第二次调用

to choose one random id and name and put it in buff struct , and second time calling

rrandom

选择新的随机值并将其放在buff结构中，如何将第二个值赋值给buff struct而不删除第一个？



我尝试过：

to choose new random value and putting it also in buff struct , how can assign the second value to buff struct without delete the first one?

What I have tried:

#include <stdio.h>    
#include <stdlib.h>   
#include <string.h>  
#define size 4

 typedef struct Org             		
{
   int  id[4]; 
   char name[4][7];  
}org;



struct buff
{
int bid[4];
char bname[4][7];
};
struct buff buf[2];

void rrandom(org select[size]){



int i,j,r=0;
for (i=0; i<1;i++){
       r = (rand() % (4 - 0)) + 0;
   for( j=0;j<4;j++){ 
    buf[i].bid[j]= select[r].id[j] ;
   strcpy(buf[i].bname[j], select[r].name[j]);
   printf("------r=%d \n" ,r);
}}
for ( int i=0; i<2 ;i++){
     
   for(int j=0;j<4;j++){ 
printf("bname %s  bid = %d \n", buf[i].bname[j], buf[i].bid[j]);

}}

}

void main(  )
{
int i,j;
org select[size]; 

sprintf(select[0].name[0],"1ello1");
sprintf(select[0].name[1],"1ello2");
sprintf(select[0].name[2],"1ello3");
sprintf(select[0].name[3],"1ello4");

sprintf(select[1].name[0],"2ello1");
sprintf(select[1].name[1],"2ello2");
sprintf(select[1].name[2],"2ello3");
sprintf(select[1].name[3],"2ello4");

sprintf(select[2].name[0],"3ello1");
sprintf(select[2].name[1],"3ello2");
sprintf(select[2].name[2],"3ello3");
sprintf(select[2].name[3],"3ello4");

sprintf(select[3].name[0],"4ello1");
sprintf(select[3].name[1],"4ello2");
sprintf(select[3].name[2],"4ello3");
sprintf(select[3].name[3],"4ello4");

sprintf(select[4].name[0],"5ello1");
sprintf(select[4].name[1],"5ello2");
sprintf(select[4].name[2],"5ello3");
sprintf(select[4].name[3],"5ello4");


   printf(" Initial id :\n");
   for(i=0;i<4 ;i++)                         
    {
        for(j=0;j< 4;j++)            			
        { 
             select[i].id[j]= j;  		
}}


rrandom(select);
rrandom(select);

for ( int i=0; i<2 ;i++){
     
   for(int j=0;j<4;j++){ 
printf("from main bname %s  bid = %d ", buf[i].bname[j], buf[i].bid[j]);

}
printf("\n\n");
}

}

推荐答案

正确的方法是修改 rrandom 函数，以便接受指向您打算修改的 struct buff 的指针。例如

The proper way to do that is modify the rrandom function in order to accept a pointer to the struct buff you intend to modify. E.g.

void rrandom( org select[], struct buff * pbuff)
{
  //...
}

然后适当地调用它，例如

And then call it appropriately, e.g.

rrandom(select, &buf[0]); // fill the first array item
rrandom(select, &buf[1])); // fill the second array item

昨天我向你解释了解决方案后，你为什么还要这样做？

见在C中使用函数的问题 [ ^ ]。

Why are you still doing this, after I explained the solution to you yesterday?
See Issue in using function in C[^].

这篇关于如何在struct中附加元素而不覆盖的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！