【C/C++学院】0828-数组与指针/内存分配/数据结构数组接口与封装

【送给在路上的程序员】

对于一个开发者而言，能够胜任系统中任意一个模块的开发是其核心价值的体现。

对于一个架构师而言，掌握各种语言的优势并可以运用到系统中，由此简化系统的开发，是其架构生涯的第一步。

对于一个开发团队而言，能在短期内开发出用户满意的软件系统是起核心竞争力的体现。

每一个程序员都不能固步自封，要多接触新的行业，新的技术领域，突破自我。

数组与指针

#include<stdio.h>#include<stdlib.h>void main1(){int a[10] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };for (int *p = a; p < a + 10; p++)//指针类型决定占4个字节{printf("\n%p,%d", p, *p);}getchar();}void  main2(){//轮询数组的时候，用指针轮询，指针可以指向某个元素的大小//指针数组，管理地址，按照顺序执行指令char *str[5] = { "calc", "notepad", "tasklist", "pause", "mspaint" };for (char **pp = str; pp < str + 5; pp++)//{system(*pp);}}void  main3(){char str[5][10] = { "calc", "notepad", "tasklist", "pause", "mspaint" };printf("%p", str); //p[1],p[2],p[3]//类型不一样for (char(*p)[10] = str; p < str + 5; p++){printf("\n %p,%s", p, p);//打印地址  字符串system((char *)p);}//char **pp = str;//for (char **pp = str; pp < str + 5; pp++)////{//system(*pp);//}system("pause");}void  main4(){char str[5][10] = { "calc", "notepad", "tasklist", "pause", "mspaint" };printf("%p,%p,%p", str, &str, *str);//指针地址的一样，但是类型不一样//str代表行地址，&str代表整个数组的地址，*str就是第一个字符的地址printf("\n%d,%d,%d", sizeof(*str), sizeof(*(&str)), sizeof(*(*str)));////求指针指向内容占多大//int num = 10;//int *p1=#//double db = 10.9;//double *  p2 = &db;//printf("%d,%d", sizeof(p1), sizeof(p2));//printf("\n%d,%d", sizeof(*p1), sizeof(*p2));system("pause");}void main5(){int a[3][4] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 };printf("%p\n", a);//int *p1 = &a[0][0];//int *p2 = p1 + 4;//printf("%d", *p2);//int *p3 = p2 - 3;//printf("\n%d", *p3);//printf("\n%d", p2 - p3); ////C语言运算规则，加法加上元素的大小×加上的数////减法就是减去元素的大小×减去的数////int *p=0x300500    p+2*(sizeof(int))=0x300508////char *p1=0x300500    p1+2*(sizeof(char))=0x300502for (int *p = &a[0][0]; p < &a[0][0] + 12; p++){if ((p - &a[0][0])%4 == 0){printf("\n");}printf("%5d", *p);}printf("\n\n\n");int (*px)[4] = a;//a是一个常量的行指针，a的类型与px等价的for (int i = 0; i < 3; i++){for (int j = 0; j < 4; j++){//printf("%5d", a[i][j]);//printf("%5d", px[i][j]);//printf("%5d", *(px[i] + j));printf("%5d", *(*(px + i) + j));}printf("\n");}getchar();}

数组与指针2

#include<stdio.h>#include<stdlib.h>int  searchmax(int a[3][4])//一维数组没有副本机制，二维数组也没有,数组作为参数都是传递地址{//printf("\nsearch=%d", sizeof(a));////int b[3][4] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 1, 2 };//printf("\nsaerch b=%d", sizeof(b));int max;//存储最大的值max = a[0][0];for (int i = 0; i < 3; i++){for (int j = 0; j < 4; j++){if (a[i][j]>max)//比较大小{max = a[i][j];//接受最大的地址}}}return max;}int  searchmaxA(int (*p)[4])//退化为一个指向有四个元素的数组的哦指针{//printf("\nsearch=%d", sizeof(a));////int b[3][4] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 1, 2 };//printf("\nsaerch b=%d", sizeof(b));int max;//存储最大的值max = p[0][0];for (int i = 0; i < 3; i++){for (int j = 0; j < 4; j++){if (p[i][j]>max)//比较大小{max = p[i][j];//接受最大的地址}}}return max;}int  searchmin(int(*p)[4]){//int  min = p[0][0];//假定第一个是最小的int  min = *(*(p+0)+0);//第一个元素的大小for (int i = 0; i < 3; i++){for (int j = 0; j < 4; j++){//if (p[i][j]<min)//比较大小//{//min= p[i][j];//求出最小的数//}if (*(*(p + i) + j) < min){min = *(*(p + i) + j);}}}return   min;}void main4(){int a[3][4] = { 1, 2, 3, 4, 5, 16, -7, 8, 9, 10, 1, 2 };printf("\nmain=%d", sizeof(a));////printf("\n%d",searchA(a));//退化为一个指针printf("\n%d", searchmin(a));system("pause");}

#include<stdio.h>#include<stdlib.h>#include<Windows.h>struct pos{int x;int y;};//struct pos  pos1[8] = { { 100, 200 },//{ 100, 0 },//{ 200, 400 } ,//{300,400},//{390,600},//{ 190, 900 },//{ 990, 100 },//{ 1390, 600 }//};struct pos  pos1[8][2] = { { { 100, 200 }, { 1000, 900 } },{ { 200, 0 }, { 900, 800 } },{ { 0, 0 }, { 800, 1300 } },{ { 1500, 200 }, {600, 900 } },{ { 800, 700 }, { 700, 800 } },{ { 300, 100 }, { 600, 700 } },{ { 900, 800 }, { 700, 700 } },{ { 100, 200 }, { 800, 800 } },};void mainx(){HWND *win = FindWindowA("Notepad", "无标题 - 记事本");if (win == NULL){return;}SetWindowPos(win, NULL, 0, 0, 100, 300, 1);for (int i = 0; i < 8; i++){//设置窗口位置大小SetWindowPos(win, NULL, pos1[i][0].x, pos1[i][0].y, pos1[i][1].x, pos1[i][1].y, 1);Sleep(3000);}system("pause");}

三维数组

#include<stdio.h>#include<stdlib.h>//int a [10]  int *p//int a[10][9] int (*p)[9]//int  a[8]  [9][10]   int (*p)[9][10]void print3(int a[3][4][5]){for (int i = 0; i < 3; i++){for (int j = 0; j < 4; j++){for (int k = 0; k < 5; k++){printf("%4d", a[i][j][k]);}printf("\n");}printf("\n\n\n");}}void print3A(int (*p)[4][5])//指针的方式{for (int i = 0; i < 3; i++){for (int j = 0; j < 4; j++){for (int k = 0; k < 5; k++){//printf("%4d", p[i][j][k]);//指针访问三维数组printf("%4d", *(*(*(p + i) + j) + k));}printf("\n");}printf("\n\n\n");}}void main(){int a[3][4][5];int num = 0;printf("%d\n", sizeof(a));//线性初始化for (int *p = &a[0][0][0]; p < &a[0][0][0] + 60; p++){*p = num;num++;}//int(*px)[4][5] = a;//等价关系print3A(a);getchar();}

内存分配

#include<stdio.h>#include<stdlib.h>void main1(){int a[1024 * 1024];//栈溢出int num = 100;//int a[num];VC数组必须常量，GCC可以是变量}//增加，删除，查询，修改int a[10];int length=10;void main2(){for (int i = 0; i < length; i++){printf("%d\n", a[i] = i);//初始化数组并打印}int num = 3;if (a[length - 1] == num)//判定最后一个{length -= 1;//长度递减}else{for (int i = 0; i < length - 1; i++) //遍历数组{if (num == a[i])//找到{for (int j = i; j < length-1; j++)//删除{a[j] = a[j + 1];//从后往前移动}length = length - 1;//长度-1break;}}}for (int i = 0; i < length; i++){printf("%d\n", a[i] );//数组并打印}system("pause");}void  main3(){int a[10] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 0 };//写C程序的时候，务必保证绝对不出错误，偶尔不报错a[10] = 11;a[11] = 12;a[102345] = 123;getchar();}void  main(){int  *p1 = (int*)malloc(sizeof(int)* 10);//只管分配，不初始化int *p2 = (int *)calloc(10,sizeof(int));//calloc会进行内存清零printf("%p,%p", p1, p2);for (int i = 0; i < 10; i++){p1[i] = i;p2[i] = i;}getchar();}

数据结构数组接口与封装

#include<stdio.h>#include<stdlib.h>void main1(){int  *p =(int *) calloc(10, sizeof(int));//分配内存printf("%p\n", p);//输出地址for (int i = 0; i < 10; i++){*(p + i) = i;//*(p+i)等价于p[i]}int *pnew = (int *)realloc(p, 100000);//变长//realloc.第一种情况，后面的内存没人用，就直接拓展变长//第二种情况，后面的内存有人用，先分配新的长度，拷贝原来的内存，释放的原来的内存printf("%p", pnew);for (int i = 10; i < 25000; i++){*(pnew + i) = i;}system("pause");}

动态数组

#include<stdio.h>#include<stdlib.h>struct data{int *p;//指针保存数组的起始点int length;//保存数组的长度int stat;//0代表无序，1代表有序从小到大，2有序从大到小int reallength;//实际分配的内存长度};struct findres{int **pp;int n;};//增加，删除，查找，修改，排序,插入void  init(struct data *pdata);//初始化void  reinit(struct data *pdata);//使用之后重新初始化void  addobject(struct data *pdata, int num);//增加一个元素void  addobjects(struct data *pdata, int *pnum, int n);//增加一个数组void  printfall(struct data *pdata);//打印所有的数据int  * finddata(struct data *pdata, int num);//返回第一个找到数据的地址void  sort(struct data *pdata, int obj);//obj=0,从小大到，否则从到小void  change(struct data *pdata, int oldnum, int newnum);//实现修改void  deleteone(struct data *pdata, int num);//删除第一个找到的数据void  deleteall(struct data *pdata, int num); //删除所有能找到的数据struct findres findadlldata(struct data *pdata, int num);//返回一片内存，包含所有找到的元素的首地址void  insert(struct data *pdata, int num, int insertnum, int headback);//数据插入//1代表前面插入，0代表后面插入

#include"动态数组.h"void init(struct data *pdata) //使用之前初始化{pdata->p = NULL;//意味着还没有初始化pdata->length = 0;//长度为0；pdata->stat = 0;//代表无序pdata->reallength = 0;//实际长度}void  reinit(struct data *pdata)//使用之后{if (pdata->p == NULL){return;}else{free(pdata->p);//释放内存pdata->p = NULL;//意味着还没有初始化pdata->length = 0;//长度为0；pdata->stat = 0;//代表无序pdata->reallength = 0;//实际长度}}//增加一个数据void  addobject(struct data *pdata, int num){if (pdata->p == NULL){pdata->p = (int *)malloc(sizeof(int));//增加一个元素pdata->length = 1;//数组标识增加一个元素pdata->reallength = 1;//实际长度pdata->p[pdata->length - 1] = num;//赋值}else{if (pdata->length == pdata->reallength){pdata->p = (int *)realloc(pdata->p, (pdata->length + 1)*sizeof(int));pdata->length += 1;//数组标识增加一个元素pdata->reallength += 1;//实际长度pdata->p[pdata->length - 1] = num;//赋值}else{pdata->length += 1;//数组标识增加一个元素pdata->p[pdata->length - 1] = num;//赋值}}}//增加一个数组void  addobjects(struct data *pdata, int *pnum, int n) //数组作为参数退化为指针{if (pdata->p == NULL){pdata->p = (int *)malloc(sizeof(int)*n);//增加N个元素pdata->length = n;//数组标识增加n个元素pdata->reallength = n;//实际长度for (int i = 0; i < n; i++){pdata->p[i] = pnum[i];//拷贝数组}}else{if (pdata->length+n <= pdata->reallength){for (int i = 0; i < n; i++){pdata->p[i + pdata->length] = pnum[i];//拷贝数组}pdata->length += n;//数组标识增加n个元素}else{pdata->p = (int *)realloc(pdata->p, (pdata->length + n)*sizeof(int));//重新分配内存for (int i = 0; i < n; i++){pdata->p[i + pdata->length] = pnum[i];//拷贝数组}pdata->length += n;//数组标识增加n个元素pdata->reallength += n;//增加长度}}}void  printfall(struct data *pdata) //打印所有的数组{for (int i = 0; i < pdata->length; i++){printf("%d\n", pdata->p[i]);//输出一个数组}}void  sort(struct data *pdata, int obj)//obj=0,从小大到，否则从da到小{if (obj == 0){for (int i = 0; i < pdata->length - 1; i++){for (int j = 0; j < pdata->length - i-1; j++){if (pdata->p[j] > pdata->p[j + 1])// j >j+1  {int temp = pdata->p[j]; //交换数据pdata->p[j] = pdata->p[j + 1];pdata->p[j + 1] = temp;}}}pdata->stat = 1;//代表从小到大}else{for (int i = 0; i < pdata->length - 1; i++){for (int j = 0; j < pdata->length - i-1; j++)//冒泡没循环一次，沉底一个极值{if (pdata->p[j] < pdata->p[j + 1])// j <j+1  {//int temp = pdata->p[j]; //交换数据//pdata->p[j] = pdata->p[j + 1];//pdata->p[j + 1] = temp;pdata->p[j] = pdata->p[j] ^ pdata->p[j + 1];pdata->p[j + 1] = pdata->p[j] ^ pdata->p[j + 1];pdata->p[j] = pdata->p[j] ^ pdata->p[j + 1];//0011  0001  3  1//p[j]0011//p[j + 1]0001// p[j]   0010//p[j + 1]0001// p[j]   0010//p[j + 1]0011//        0001  a=a^b,b=a^b.a=a^b;}}}pdata->stat = 2;//代表从大到小}}int  * finddata(struct data *pdata, int num){if (pdata->stat == 0){for (int i = 0; i < pdata->length; i++)//顺序循环{printf("查找第%d次\n", i);if (num == pdata->p[i])//判定是否相等{return  &pdata->p[i];//返回一个地址break;//跳出循环}}return NULL;}else if (pdata->stat == 1) //二分查找法//从小到da{int  shang = 0;//shangint xia = pdata->length - 1;//下while (shang <= xia)//循环终止条件, {int zhong = (shang + xia) / 2;printf("%d,%d,%d\n", shang, zhong, xia);if (pdata->p[zhong] == num){return  &pdata->p[zhong];//返回地址}else if (pdata->p[zhong] >num){xia = zhong - 1;}else if (pdata->p[zhong]<num){shang = zhong + 1;}}return NULL;}else{int  shang = 0;//shangint xia = pdata->length - 1;//下while (shang <= xia)//循环终止条件, {int zhong = (shang + xia) / 2;printf("%d,%d,%d\n", shang, zhong, xia);if (pdata->p[zhong] == num){return  &pdata->p[zhong];//返回地址}else if (pdata->p[zhong] >num){//xia = zhong - 1;shang = zhong + 1;}else if (pdata->p[zhong]<num){//shang = zhong + 1;xia = zhong - 1;}}return NULL;}}void  change(struct data *pdata, int oldnum, int newnum)//实现修改{int *p = finddata(pdata, oldnum);if (p == NULL){printf("修改失败，没有找到");return;}else{*p = newnum;//修改数据}}////1代表前面插入，0代表后面插入void  insert(struct data *pdata, int num, int insertnum, int headback)//数据插入{int *p = finddata(pdata, num);//查找数据if (p == NULL){return ;//没有找到}else{//找到,前面插入 ，否则后面插入if (headback==1){if (pdata->length<pdata->reallength)//不需要分配{int  curr = p - pdata->p;//获取要插入位置的下标for (int i = pdata->length - 1; i>=curr; i--){pdata->p[i + 1] = pdata->p[i];//从后向前移动}pdata->p[curr] = insertnum;//实现插入，前面插入pdata->length++;//长度加1}else{int  curr = p - pdata->p;//获取要插入位置的下标pdata->p = (int *)realloc(pdata->p, (pdata->length + 1)*sizeof(int));//增加分配内存pdata->reallength++;//实际长度+1；for (int i = pdata->length - 1; i >= curr; i--){pdata->p[i + 1] = pdata->p[i];//从后向前移动}pdata->p[curr] = insertnum;//实现插入，前面插入pdata->length++;//长度加1}}else{if (pdata->length<pdata->reallength)//不需要分配{int  curr = p - pdata->p;//获取要插入位置的下标for (int i = pdata->length - 1; i > curr; i--)//实现移动{pdata->p[i + 1] = pdata->p[i];//从后向前移动}pdata->p[curr+1] = insertnum;//实现插入，hou插入pdata->length++;//长度加1}else{int  curr = p - pdata->p;//获取要插入位置的下标pdata->p = (int *)realloc(pdata->p, (pdata->length + 1)*sizeof(int));//增加分配内存pdata->reallength++;//实际长度+1；for (int i = pdata->length - 1; i > curr; i--)//实现移动{pdata->p[i + 1] = pdata->p[i];//从后向前移动}pdata->p[curr + 1] = insertnum;//实现插入，hou插入pdata->length++;//长度加1}}}}//删除void  deleteone(struct data *pdata, int num){int *p = finddata(pdata, num);//查找数据if (p == NULL){return ;//没有找到,删除，}else{int  curr = p - pdata->p;//cur就是要删除的下标//printf("\n%d,%p", *p, p);//printf("\n%d,%p", pdata->p[curr], &pdata->p[curr]);//输出数据for (int i = curr; i < pdata->length - 1; i++){pdata->p[i] = pdata->p[i + 1];//从后向前移动}pdata->length -= 1;//数组元素减去1}}//删除全部void  deleteall(struct data *pdata, int num) //删除所有能找到的数据{for (int *p = finddata(pdata, num); p != NULL; p = finddata(pdata, num)){int  curr = p - pdata->p;//cur就是要删除的下标//printf("\n%d,%p", *p, p);//printf("\n%d,%p", pdata->p[curr], &pdata->p[curr]);//输出数据for (int i = curr; i < pdata->length - 1; i++){pdata->p[i] = pdata->p[i + 1];//从后向前移动}pdata->length -= 1;//数组元素减去1}}int * find(int *p, int num,int n )//从一个地址开始，N个范围之内找到{for (int i = 0; i < n; i++)//循环{if (p[i] == num)//判断{return p + i;//返回找到的地址break;}}return NULL;//代表没有找到}struct findres findadlldata(struct data *pdata, int num){struct findres  res1;//构建结构体变量int i = 0; //统计找到多少个。for (int *p = find(pdata->p, num, pdata->length - 1);p!=NULL; p = find(p+1, num, (pdata->length - 1)-(p-pdata->p))){i++;}res1.n = i;//长度int **pint = (int **)malloc(sizeof(int *)* i);//指针数组res1.pp = pint;for (int *p = find(pdata->p, num, pdata->length - 1),j=0; p != NULL;j++, p = find(p + 1, num, (pdata->length - 1) - (p - pdata->p))){pint[j] = p;//循环赋值//printf("\n%p,%d\n", pint[j], *pint[j]);}return res1;}

数组库的测试

#include<stdio.h>#include<stdlib.h>#include"动态数组.h"void main(){int a[10] = { 231, 112, 1233, 14123, 523, 112, 71, 18, 29, 112 };struct data  data1;init(&data1);addobject(&data1, 10);addobject(&data1, 11);addobject(&data1, 12);//reinit(&data1);addobjects(&data1, a, 10);printfall(&data1);insert(&data1, 1233, 1988, 1);insert(&data1, 1233, 1998, 0);printfall(&data1);system("pause");}void main2(){int a[10] = { 231, 112, 1233, 14123, 523, 112, 71, 18, 29, 112 };struct data  data1;init(&data1);addobject(&data1, 10);addobject(&data1, 11);addobject(&data1, 12);//reinit(&data1);addobjects(&data1, a, 10);printfall(&data1);struct findres  resn=  findadlldata(&data1, 112);//查找for (int i = 0; i < resn.n; i++){printf("\nresn %p,%d\n", *(resn.pp+i), **(resn.pp+i));//二级指针遍历指针数组}free(resn.pp);//释放内存printfall(&data1);system("pause");}void main1(){int a[10] = { 231, 112, 1233, 14123, 523,116, 71, 18, 29, 110 };struct data  data1;init(&data1);addobject(&data1, 10);addobject(&data1, 11);addobject(&data1, 12);//reinit(&data1);addobjects(&data1, a, 10);printfall(&data1);int *pfind = finddata(&data1, 1101);//查找if (pfind != NULL){printf("%d,%p", *pfind, pfind);//输出查找结果}else{printf("没有找到奥");}{printf("\n\n");sort(&data1, 0);printfall(&data1);int *pfind = finddata(&data1, 523);//查找if (pfind != NULL){printf("%d,%p", *pfind, pfind);//输出查找结果}else{printf("没有找到奥");}}{printf("\n\n");sort(&data1, 1);printfall(&data1);int *pfind = finddata(&data1, 523);//查找if (pfind != NULL){printf("%d,%p", *pfind, pfind);//输出查找结果}else{printf("没有找到奥");}}getchar();}

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