Dynamic sequence table + OJ

A sequence table is essentially an array , This paper simply realizes the addition of dynamic sequence table , Delete , check , Change .

The key is to learn the idea of sequential table implementation , The sequence table is very detailed , Think about it in many ways .

// Sequential header file 
#pragma once

#include <stdio.h>
#include <assert.h>
#include <stdlib.h>
// requirement ： Stored data from 0 Start , Sequential continuous storage 
// The essence of a sequential table is an array , An array that can be expanded 

//#define N 100
//typedef struct SeqList
//{
//	int a[N];
//	int size;// Record the number of data stored 
//}SeqList;
// Static sequence table , There are defects 


// Dynamic sequence table 
typedef int SLDataType;

typedef struct SeqList
{
	SLDataType* a;
	int size;    // Number of storage 
	int capacity;// Storage capacity 
}SeqList;

// Sequence table initialization 
void SeqListInit(SeqList* psl);

// Destroy the sequence table 
void SeqListDestroy(SeqList* psl);

// Tail insertion 
void SeqListPushBack(SeqList* psl, SLDataType x);

// Deletion at the end 
void SeqListPopBack(SeqList* psl);

// Head insertion 
void SeqListPushFront(SeqList* psl, SLDataType x);

// Head deletion 
void SeqListPopFront(SeqList* psl);

// Head insertion 
void SeqListPopFront(SeqList* psl);

// Print 
void SeqListPrint(SeqList* psl);

// Check whether expansion is needed 
void SeqListCheckCapacity(SeqList* psl);

// stay pos Position insert x
void SeqListInsert(SeqList* psl, int pos, SLDataType x);

// stay pos Location delete data 
void SeqListErase(SeqList* psl, int pos);

// lookup 
int SeqListFind(SeqList* psl, SLDataType x);

#include "SeqList.h"

// initialization 
void SeqListInit(SeqList* psl)
{
	assert(psl);
	psl->a = NULL;
	psl->size = 0;
	psl->capacity = 0;
}

// The destruction 
void SeqListDestroy(SeqList* psl)
{
	assert(psl);
	free(psl->a);
	psl->a = NULL;
	psl->capacity = psl->size = 0;
}

// Check whether expansion is needed 
void SeqListCheckCapacity(SeqList* psl)
{
	assert(psl);
	// If there is not enough space, it needs to be expanded 
	if (psl->size == psl->capacity)
	{
		size_t newcapacity = psl->capacity == 0 ? 4 : psl->capacity * 2;
		SLDataType* tmp = realloc(psl->a, sizeof(SLDataType) * newcapacity);
		if (tmp == NULL)
		{
			printf("realloc fail\n");
			exit(-1);
		}
		else
		{
			psl->a = tmp;
			psl->capacity = (int)newcapacity;
		}
	}
}

// Tail insertion 
void SeqListPushBack(SeqList* psl, SLDataType x)
{
	assert(psl);
	SeqListCheckCapacity(psl);
	// When there is enough space 
	psl->a[psl->size] = x;
	psl->size++;
}

// Deletion at the end 
void SeqListPopBack(SeqList* psl)
{
	assert(psl);
	// Some details ,size Greater than 0 Just delete , Otherwise, delete it to a negative number 
	if (psl->size > 0)
	{
		psl->size--;
	}
}

// Head insertion 
void SeqListPushFront(SeqList* psl, SLDataType x)
{
	assert(psl);
	SeqListCheckCapacity(psl);
	// Ideas ： Move all elements backward to cover 
	size_t end = psl->size - 1;
	while (end >= 0)
	{
		psl->a[end + 1] = psl->a[end];
		end--;
	}
	psl->a[0] = x;
	psl->size++;
}

// Head deletion 
void SeqListPopFront(SeqList* psl)
{
	assert(psl);
	if (psl->size > 0)
	{
		size_t begin = 1;
		while (begin < psl->size)
		{
			psl->a[begin - 1] = psl->a[begin];
			begin++;
		}
		psl->size--;
	}
}

// Print 
void SeqListPrint(SeqList* psl)
{
	assert(psl);
	for (int i = 0; i < psl->size; i++)
	{
		printf("%d ", psl->a[i]);
	}
	printf("\n");
}

// stay pos Position insert element 
void SeqListInsert(SeqList* psl, size_t pos, SLDataType x)
{
	assert(psl);
	SeqListCheckCapacity(psl);
	int end = psl->size;
	while (end > pos)
	{
		psl->a[end] = psl->a[end - 1];
		end--;
	}
	psl->a[pos] = x;
	psl->size++;
}

// stay pos Position delete element 
void SeqListErase(SeqList* psl, size_t pos)
{
	// Place the subscript at pos Delete the elements of 
	assert(psl);
	if (psl->size > 0)
	{
		int begin = (int)pos;
		while (begin < psl->size)
		{
			psl->a[begin] = psl->a[begin + 1];
			begin++;
		}
		psl->size--;
	}
}

// lookup , Find the return subscript , No return found -1
int SeqListFind(SeqList* psl, SLDataType x)
{
	assert(psl);
	for (int i = 0; i < psl->size; i++)
	{
		if (psl->a[i] == x)
		{
			return i;
		}
	}
	return -1;
}

  Pay attention to the following points in the sequence table ：

1. When writing each interface , Add assertions , Easy to find errors

2. Adding data （ Head insertion , Tail insertion ） when , Be sure to check whether there is enough space , call SeqListCheckCapacity function

3. Deleting data （ Head deletion , Deletion at the end ） when , Make sure that the array size cannot be negative

4.SeqListInsert It can replace the head plug , Tail insertion ;SeqListErase Can replace header deletion , Deletion at the end . But check if it's feasible

The order sheet OJ 

  Method ： Double pointer

Spatial complexity O（1）

Time complexity O（N）

  Realization ：

1.src Location is not val, Put it on dst Location , then src++,dst++

2.src Location is val,src++