带有C的数组元素出现意外结果

I am trying to insert an integer if array position is equal to 3 but unfortunately when I am printing my array a I am getting absured results like this:

我试图插入一个整数，如果数组位置等于3但不幸的是，当我打印我的数组时，我得到了这样的结果：

   0
   0
   2

whereas, the result expected is:

而预期的结果是：

My code is:

我的代码是：

#include<stdio.h>
int substitute_and_sum(int *a, int len)
{

    int sum = 0, i;
    for (i = 0; i < 5; i++)
    {
        if (i == 3)
        {
            a[i] = 128;
        }
    }

    printf("%d\n", *a);
    return 0;
}

int main()
{

    int arr[] = { 0, 0, 2, 0, 0 };
    int j = 5, i;

    for (i = 0; i < 5; i++)
    {
        substitute_and_sum(&arr[i], j);
    }
}

5 个解决方案

#1

one for loop is enough

一个for循环就足够了

#include<stdio.h>
int substitute_and_sum(int* a, int len) {

int sum =0, i; 
for(i=0;i< len;i++)
{
 if(i==3)
        { 
     a[i] = 128;
    }
 printf("%d\n" , a[i]);  
}

 return 0;
}

 int main(){

 int arr[]={0,0,2,0,0};
 int j=5,i;
  substitute_and_sum(&arr[i],j);
}

replace 5 with len otherwise what is the point of the argument and the last printf() is pointless because it only prints the value of the first element;

用len替换5，否则参数的重点是什么，最后一个printf（）是没有意义的，因为它只打印第一个元素的值;

#2

You have two for loops which don't play well together. Remove one or the other. For example:

你有两个for循环，它们不能很好地结合在一起。删除其中一个。例如：

int main()
{

    int arr[] = { 0, 0, 2, 0, 0 };
    int j = 5;

    substitute_and_sum(arr, j);
    for (int i = 0; i < 5; i++)
    {
        printf("%d\n", a[i]);
    }
}

Note that I moved the printf into main. Your existing program is pretty weird.

请注意，我将printf移动到main。你现有的程序很奇怪。

#3

You just need to call like following

你只需要像下面这样打电话

int main(){

 int arr[]={0,0,2,0,0};
 int j=5,i;

 //for(i=0;i<5;i++)
 //{
  substitute_and_sum(arr,j);
 //}
}

Or use :-

或使用： -

void substitute_and_sum(int *a)
{   
    *a = 128;
}

And in main :

在主要：

for (i = 0; i < 5; i++)
{
    if (i == 2) //Note its index 2, not 3
    substitute_and_sum(&arr[i]);
}

#4

You loop over your array in both functions, just do it in one of them.

您可以在两个函数中遍历数组，只需在其中一个函数中执行。

#5

this works, whenever you send individual value of the array make it an habit of sending its index, if required for example in case like yours.

这是有效的，每当你发送数组的单个值时，就养成发送索引的习惯，如果需要，例如像你的那样。

 #include<stdio.h>
    int substitute_and_sum(int *a, int i)
    {

            if (i == 3)


 {
            *a = 128;
        }
    printf("%d\n", *a);
    return 0;
}

int main()
{

    int arr[] = { 0, 0, 2, 0, 0 };
    int  i;

    for (i = 0; i < 5; i++)
    {
        substitute_and_sum(&arr[i], i);
    }
}

#1