线性表——长度为n的线性表A采用顺序存储结构，删除所有值为item的数据元素 时间复杂度为O(n)、空间复杂度为O(1)

 

//“MergeList.h
#include <iostream>

#define MAXSIZE 100
#define ElemType int

using namespace std;

typedef struct
{
    ElemType *elem;
    int length;
} SqList;

string InitList(SqList &L){
    L.elem = new ElemType[MAXSIZE];
    if(!L.elem) return "OVERFLOW";
    L.length = 0;
    return "OK";
}

ElemType GetElem(SqList L,int i ){
    if(i<1 || i > L.length) return 0;
    return L.elem[i-1];
}

int LocalElem(SqList L,ElemType e){
    for(int i = 0;i<L.length;i++){
        if(L.elem[i] == e) return i+1;
    }
    return 0;
}

string ListInsert(SqList &L,int i,ElemType e){
    //if(i<1||i>L.length) return "ERROR";
    if(L.length == MAXSIZE) return "ERROR";
    for(int j=L.length-1;j>i-1;j--)
        L.elem[j+1] = L.elem[j];
    L.elem[i-1] = e;
    ++L.length;
    return "OK";
}

string ListDelete(SqList &L,int i ){
    if(i<1||i>L.length) return "ERROR";
    for(int j = i-1;j<L.length;j++)
        L.elem[j] = L.elem[j+1];
    --L.length;
    return "OK";
}

void ShowList(SqList L){
    cout << "show the list"<<endl;
    for(int i=0; i<L.length;i++){
        cout << L.elem[i] <<" ";
    }
}

string FillListWithNum(SqList &L,int i){
    for(int j=1;j<=i;j++){
        ElemType p;
        cin>>p;
        ListInsert(L,j,p);
    }
    return "OK";

}

// ShowList(L);

// cout << "Delete"<<endl;
// cout << ListDelete(L,2);
// ShowList(L);

// cout<<"!";

// return 0;
// }

 

 

#include<iostream>
#include"MergeList.h"
using namespace std;

/*
 长度为n的线性表A采用顺序存储结构，删除所有值为item的数据元素
 时间复杂度为O(n)、空间复杂度为O(1)

*/

int main(){

    SqList LA;

    InitList(LA);

    cout <<"How long"<<endl;
    int num ;
    cin >> num;
    FillListWithNum(LA,num);


    ElemType item = 5 ;

    int step = 0;                //记录保留元素需要前移的步数
    for(int i=0;i<num;i++){
        if(LA.elem[i] == item){  //循环里操作步骤与n无关，时间复杂度为O(1)
            step++;
            LA.length--;
        }else
        {
            LA.elem[i-step] = LA.elem[i];
        }
     }
        ShowList(LA);
        system("pause");
        return 0;
    }

如果遍历到与item值相同的，调用Delete函数，将后续的元素前移，则每一次遍历的时间复杂度为O(n)