2.2 comprehensive application questions - sequence table

subject 1： Order table delete elements

subject ： Delete the element with the lowest value from the sequence table （ Suppose only ） And the value of the deleted element is returned by the function , The empty position is filled by the last element , If the sequence table is empty, an error message will be displayed and the operation will be exited .

/**
 * @brief 
 *  subject ：  Delete the element with the lowest value from the sequence table （ Suppose only ）
 *  And the value of the deleted element is returned by the function ,
 *  The empty position is filled by the last element ,
 *  If the sequence table is empty, an error message will be displayed and the operation will be exited .
 *  Ideas ：
 *  The values of the sequence table are entered by the keyboard 
 *  hypothesis 0 No. data minimum , Compare with the following data , Finally, find the minimum value , Delete minimum , And fill in the last element here , Then delete the last element , Achieve the purpose of reducing the length .
 */

#include <stdio.h>
#define MaxSize 10 // Defines the maximum length of a linear table 

typedef int ElemType;// Define data types 

// Type definition of sequence table , The sequence table is Sqlist, Name of the sequence table ：L
typedef struct {
    ElemType data[MaxSize];// Elements of a sequence table 
    int length;// The current length of the sequence table 
}SqList; 

// Define delete minimum function 
void Del_Min(SqList L, ElemType value)
{
    //value Is the deleted value 

    if (L.length==0)
    {
        printf(" Wrong information \n");
	    value = 0;
    }
    value = L.data[0];
    int pos = 0;
    for (int i = 1; i < L.length; i++)
    {
       if (L.data[i]<value)
       {
            value = L.data[i];
            pos = i;
       }  
    }
    if (pos < L.length-1)
    {
        L.data[pos]=L.data[L.length-1];// The empty position is filled by the last element 
        L.length--;
    }
    printf(" The minimum value in the sequence table is : %d\n",value);
    printf(" The remaining elements of the sequence table are :\n");
    for(int i = 0; i < L.length;i++){
        printf("%d ",L.data[i]);
    }
}

int main()
{
    SqList L;
    L.length = 0;
    for (int i = 0; i < MaxSize; i++)
    {
        scanf("%d",&L.data[i]);
        L.length++;
    }

    int a;
    Del_Min(L,a);// Call function 

    printf("\n");
    return 0;  
}

Searched C Language version of the code , Everyone chose the definition bool Function of type , The return value is true Or is it false, however C Language only in c99 in the future , And add #include <stdbools> After this header , Can be used bool type .

In others' code , Also used. &—— quote .

Among them & Presentation reference , Instead of taking the address . The quotation is C++ Yes C An important supplement to . The reference of a variable is the alias of the variable , Speaking in a popular way, it's another name . Both point to the same address at the same time , A numeric variable , Another value will also change . It is also understandable if variables b It's a variable. a References to So no matter a,b Any one of the values changes , Another corresponding change , When declaring a reference , It must be initialized at the same time , That is, declare which variable it represents . Please note that ： Because references are not independent variables , The compilation system does not assign storage units to it separately , therefore When creating a reference, only the declaration is undefined , Just declare its relationship with an original variable . After declaring a reference to a variable , During the execution of this function , This reference is always associated with the variable it represents , It can no longer be used as an alias for other variables .

however , It is a pity ： pure C In language , There is no reference , In this case, pointers can be used instead of references . I don't want to use pointer variables yet , therefore , This writing failed .