C语言练习 -- 8

#define _CRT_SECURE_NO_WARNINGS 1

#include<stdio.h>

void test(int arr[])
{
    int sz = sizeof(arr) / sizeof(arr[0]);
    printf("%d\n", sz);
}

int main()
{
    int arr[10] = { 0 };
    test(arr);
    return 0;
}

int main()
{
    char arr[] = "abcdef";
    char* pc = arr;
    printf("%s\n", arr);
    printf("%s\n", pc);
    return 0;
}


int main()
{
    char arr1[] = "abcdef";
    char arr2[] = "acbdef";
    char* p1 = "abcdef";
    char* p2 = "abcdef";

    if (p1 == p2)
    {
        printf("hehe\n");
    }
    else
    {
        printf("haha\n");
    }

    //if (arr1 == arr2)
    //{
    //    printf("hehe\n");
    //}
    //else
    //{
    //    printf("haha\n");
    //}
    return 0;
}


int main()
{
    int arr[10] = { 0 };//整型数组
    char ch[5] = { 0 };//字符数组
    int* parr[4];//存放整型指针的数组 - 指针数组
    char* pch[5];//存放字符指针的数组 - 指针数组
    return 0;
}

int main()
{
    int a = 10;
    int b = 20;
    int c = 30;
    int d = 40;
    int* arr[4] = { &a, & b,&c,&d };
    int i = 0;
    for (i = 0; i < 4; i++)
    {
        printf("%d ", *(arr[i]));
    }
    return 0;
}


int main()
{
    int arr1[] = { 1,2,3,4,5 };
    int arr2[] = { 2,3,4,5,6 };
    int arr3[] = { 3,4,5,6,7 };
    int* parr[] = { arr1,arr2,arr3 };
    int i = 0;
    for (i = 0; i < 3; i++)
    {
        int j = 0;
        for (j = 0; j < 5; j++)
        {
            printf("%d ", *(parr[i] + j));
        }
        printf("\n");
    }
    return 0;
}



数组指针 - 指针

int main()
{
    int* p = NULL;//整型指针 - 指向整型的指针 - 可以存放整型的地址
    char* pc = NULL;//pc是字符指针 - 指向字符的指针 - 可以存放字符的地址
    //数组指针 - 指向数组的指针 - 可以存放数组的地址
    int arr[10] = { 0 };
    //arr - 首元素地址
    //&arr[0] - 首元素地址
    //&arr - 数组的地址

    int arr[10] = { 1,2,3,4,5,6,7,8,9,10 };
    int (* p)[10] = &arr;//数组的地址要存起来
    //上面的p就是数组指针
    return 0;
}


int main()
{
    char* arr[5];
    char*(*pa)[5] = &arr;
    return 0;
}


int main()
{
    int arr[10] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
    int* p = arr;
    int i = 0;
    for (i = 0; i < 10; i++)
    {
        printf("%d ", *(p + i));
    }

    int(*pa)[10] = &arr;
    int i = 0;
    for (i = 0; i < 10; i++)
    {
       printf("%d ",*( * pa + i));//*pa == arr
    }

    for (i = 0; i < 10; i++)
    {
        printf("%d ",(*pa)[i]);
    }
    return 0;
}

//参数是数组的形式
void print1(int arr[3][5], int x, int y)
{
    int i = 0;
    int j = 0;
    for (i = 0; i < x; i++)
    {
        for (j = 0; j < y; j++)
        {
            printf("%d ", arr[i][j]);
        }
        printf("\n");
    }
}

//参数是指针的形式
void print2(int (*p)[5], int x, int y)
{
    int i = 0;
    for (i = 0; i < x; i++)
    {
        int j = 0;
        for (j = 0; j < y; j++)
        {
            //printf("%d ", *(*(p + i) + j));
            printf("%d ", ( * (p + i))[j]);
        }
        printf("\n");
    }
}


int main()
{
    int arr[3][5] = { {1,2,3,4,5},{2,3,4,5,6},{3,4,5,6,7} };

    print1(arr, 3, 5);//arr - 数组名 - 数组名就是首元素地址
    print2(arr, 3, 5);
    int arr[10] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
    int i = 0;
    int* p = arr;
    for (i = 0; i < 10; i++)
    {
        printf("%d ", p[i]);
        printf("%d ", *(p + i));
        printf("%d ", arr[i]);
        printf("%d ", *(arr + i));
    }
    return 0;
}


int arr[5];//arr是一个5个元素的整型数组
int* parr1[10];//parr1是一个数组，数组有10个元素，每个元素的类型是int*，parr1是指针数组
int(*parr2)[10];//parr2是一个指针，该指针指向了一个数组，数组有10个元素，每个元素的类型是int,parr2是数组指针
int(*parr3[10])[5];//parr3是一个数组，该数组有10个元素，每个元素是一个指针 - 数组指针,该数组指针指向的数组有5个元素，每个元素是int