C语言进阶课程学习记录-第27课

C语言进阶课程学习记录-第27课 - 数组的本质分析

- 数组
- 实验-数组元素个数的指定
- 实验-数组地址与数组首元素地址
- 实验-指针与数组地址的区别
- 小结

本文学习自狄泰软件学院唐佐林老师的 C语言进阶课程，图片全部来源于课程PPT，仅用于个人学习记录

数组

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实验-数组元素个数的指定

#include <stdio.h>

int main()
{
    int a[5] = {1, 2};
    int b[] = {1, 2};
    int c[5] = {0};

    printf("a[2] = %d\n", a[2]);
    printf("a[3] = %d\n", a[3]);
    printf("a[4] = %d\n", a[4]);

    printf("sizeof(a) = %d\n", sizeof(a));
    printf("sizeof(b) = %d\n", sizeof(b));
    printf("count for a: %d\n", sizeof(a)/sizeof(int));
    printf("count for b: %d\n", sizeof(b)/sizeof(int));

    printf("c[0] = %d\n", c[0]);
    printf("c[1] = %d\n", c[1]);

    printf("c[2] = %d\n", c[2]);
    printf("c[3] = %d\n", c[3]);
    printf("c[4] = %d\n", c[4]);

    return 0;
}
/*
output:

a[2] = 0
a[3] = 0
a[4] = 0
sizeof(a) = 20
sizeof(b) = 8
count for a: 5
count for b: 2
c[0] = 0
c[1] = 0
c[2] = 0
c[3] = 0
c[4] = 0



*/

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实验-数组地址与数组首元素地址

#include <stdio.h>

int main()
{
    int a[5] = { 0 };

    printf("a = %p\n", a);
    printf("&a = %p\n", &a);
    printf("&a[0] = %p\n", &a[0]);

    return 0;
}
/*
output:

a = 0060FEEC
&a = 0060FEEC
&a[0] = 0060FEEC



*/

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实验-指针与数组地址的区别

#include <stdio.h>
int main()
{
    int a[5] = {0};
    int b[2];
    int* p = NULL;

    p = a;

    printf("a = %p\n", a);
    printf("p = %p\n", p);
    printf("&p = %p\n", &p);
    printf("sizeof(a) = %d\n", sizeof(a));
    printf("sizeof(p) = %d\n", sizeof(p));

    printf("\n");

    p = b;

    printf("b = %p\n", b);
    printf("p = %p\n", p);
    printf("&p = %p\n", &p);
    printf("sizeof(b) = %d\n", sizeof(b));
    printf("sizeof(p) = %d\n", sizeof(p));

    //b = a;//error: incompatible types when assigning to type 'int[2]' from type 'int *'|

    return 0;
}
/*
output:

a = 0060FEEC
p = 0060FEEC
&p = 0060FEE0
sizeof(a) = 20
sizeof(p) = 4

b = 0060FEE4
p = 0060FEE4
&p = 0060FEE0
sizeof(b) = 8
sizeof(p) = 4


*/