c语言：数组、指针、地址

#include <stdio.h>
#include <stdlib.h>


int main(){
    
    int a[5][5], i;
    int *p = (int *)(a + 1);
    printf("-----------------------------\n");
    printf("a: %p, a + 1: %p\n", a, a + 1);
    printf("p: %p, p + 1: %p\n", p, p + 1);
    printf("-----------------------------\n");
    printf("char: %ld, int: %ld, float: %ld,\r\n double: %ld, long: %ld longlong: %ld\n",
        sizeof(char), sizeof(int), sizeof(float), sizeof(double), sizeof(long), sizeof(long long));
    printf("char*: %ld, int*: %ld, float*: %ld,\r\n double*: %ld, long*: %ld longlong*: %ld\n",
        sizeof(char*), sizeof(int*), sizeof(float*), sizeof(double*), sizeof(long*), sizeof(long long*));
    printf("-------------------------------\n");
    char A[5] = {'1', '2', '3', '3', '5'};
    char* aa = A;

    printf("A: %p, A + 1: %p\n", A, ++aa);
    int B = 10;
    int* C = &B;
    printf("C: %p, C + 1: %p\n", C, C + 1);
    printf("-------------------------------\n");
    for(int j = 0; j < 5; j ++)
        for(int k = 0; k < 5; k ++) a[j][k] = 0;
    for (i = 0;i < 20; i++) *p++=i;

    for(int j = 0; j < 5; j ++){
        for(int k = 0; k < 5; k ++){
            printf("a[%d][%d]: %d ", j, k, a[j][k]);
        }
        printf("\n");
    }
    printf("%d\n", a[3][2]);
    
    return 0;
}

可以看出在Linux操作系统中是以字节为最小单位，对于一维数组来说其地址+1与二维数组其地址+1不一样，目前来看是+本数据类型的字节数，二维数组地址是连续的，指针都是八字节

#include <stdio.h>
#include <stdlib.h>

int main(){

char a[] = "hello";
char*p = a;
a[0] = 'd';
printf("%s %s\n", a, p);
printf("sizeof(a): %ld, sizeof(p): %ld\n", sizeof(a), sizeof(p));

}

sizeof是计算结束符的，对于a数组来说hello是被复制进a的，a内成员可以改动