c语言中多维数组的指针表示

学c的时候碰见了下面这道题
修改下面的程序，让它从数组计算变成指针计算：

/* rain.c  -- finds yearly totals, yearly average, and monthly
 average for several years of rainfall data */
#include <stdio.h>
#define MONTHS 12    // number of months in a year
#define YEARS   5    // number of years of data
int main(void)
{
    // initializing rainfall data for 2010 - 2014
    const float rain[YEARS][MONTHS] =
    {
        {4.3,4.3,4.3,3.0,2.0,1.2,0.2,0.2,0.4,2.4,3.5,6.6},
        {8.5,8.2,1.2,1.6,2.4,0.0,5.2,0.9,0.3,0.9,1.4,7.3},
        {9.1,8.5,6.7,4.3,2.1,0.8,0.2,0.2,1.1,2.3,6.1,8.4},
        {7.2,9.9,8.4,3.3,1.2,0.8,0.4,0.0,0.6,1.7,4.3,6.2},
        {7.6,5.6,3.8,2.8,3.8,0.2,0.0,0.0,0.0,1.3,2.6,5.2}
    };
    int year, month;
    float subtot, total;
    
    printf(" YEAR    RAINFALL  (inches)\n");
    for (year = 0, total = 0; year < YEARS; year++)
    {             // for each year, sum rainfall for each month
        for (month = 0, subtot = 0; month < MONTHS; month++)
            subtot += rain[year][month];
        printf("%5d %15.1f\n", 2010 + year, subtot);
        total += subtot; // total for all years
    }
    printf("\nThe yearly average is %.1f inches.\n\n",
           total/YEARS);
    printf("MONTHLY AVERAGES:\n\n");
    printf(" Jan  Feb  Mar  Apr  May  Jun  Jul  Aug  Sep  Oct ");
    printf(" Nov  Dec\n");
    
    for (month = 0; month < MONTHS; month++)
    {             // for each month, sum rainfall over years
        for (year = 0, subtot =0; year < YEARS; year++)
            subtot += rain[year][month];
        printf("%4.1f ", subtot/YEARS);
    }
    printf("\n");
    
    return 0;
}

实则就是考验数组和指针的关系，即从数组表示变成指针表示。为了新建了一个测试文件：

#include <stdio.h>
#define Size 5

int print_all_arr(const float test[Size][Size]);
int print_test(const float *test,char test_s[]);

int main(void)
{
    const float test[Size][Size] =
        {
            {0.0, 0.1, 0.2, 0.3, 0.4},
            {1.0, 1.1, 1.2, 1.3, 1.4},
            {2.0, 2.1, 2.2, 2.3, 2.4},
            {3.0, 3.1, 3.2, 3.3, 3.4},
            {4.0, 4.1, 4.2, 4.3, 4.4}};
    print_all_arr(test);
    printf("开始数组表示:\n");
    print_test(&test[1][2],"test[1][2]");
    print_test(test[1],"test[1]");
    print_test(test,"test");
    printf("开始指针表示:\n");
    print_test(&test,"test");
    print_test(&*(test+1),"*(test+1)");
    print_test(&*(*(test + 1) + 2),"*(*(test + 1) + 2)");
    return 0;
}

int print_all_arr(const float test[Size][Size])
{
    for (int i = 0; i < Size; i++)
    {
        for (int n = 0; n < Size; n++)
        {
            printf("%f  ", test[i][n]);
            // printf("%i %i  ", i, n);
            printf("%p  | ", &test[i][n]);
        }

        printf("\n");
    }
}

int print_test(const float *test,char test_s[])
{
    printf("它的值为:%f     地址为%p    使用表达式：%s\n", *test, test,test_s);
}

此程序输出为：

0.000000  0x7ffe53ddb480  | 0.100000  0x7ffe53ddb484  | 0.200000  0x7ffe53ddb488  | 0.300000  0x7ffe53ddb48c  | 0.400000  0x7ffe53ddb490  | 
1.000000  0x7ffe53ddb494  | 1.100000  0x7ffe53ddb498  | 1.200000  0x7ffe53ddb49c  | 1.300000  0x7ffe53ddb4a0  | 1.400000  0x7ffe53ddb4a4  | 
2.000000  0x7ffe53ddb4a8  | 2.100000  0x7ffe53ddb4ac  | 2.200000  0x7ffe53ddb4b0  | 2.300000  0x7ffe53ddb4b4  | 2.400000  0x7ffe53ddb4b8  | 
3.000000  0x7ffe53ddb4bc  | 3.100000  0x7ffe53ddb4c0  | 3.200000  0x7ffe53ddb4c4  | 3.300000  0x7ffe53ddb4c8  | 3.400000  0x7ffe53ddb4cc  | 
4.000000  0x7ffe53ddb4d0  | 4.100000  0x7ffe53ddb4d4  | 4.200000  0x7ffe53ddb4d8  | 4.300000  0x7ffe53ddb4dc  | 4.400000  0x7ffe53ddb4e0  | 
开始数组表示:
它的值为:1.200000     地址为0x7ffe53ddb49c    使用表达式：test[1][2]
它的值为:1.000000     地址为0x7ffe53ddb494    使用表达式：test[1]
它的值为:0.000000     地址为0x7ffe53ddb480    使用表达式：test
开始指针表示:
它的值为:0.000000     地址为0x7ffe53ddb480    使用表达式：test
它的值为:1.000000     地址为0x7ffe53ddb494    使用表达式：*(test+1)
它的值为:1.200000     地址为0x7ffe53ddb49c    使用表达式：*(*(test + 1) + 2)

也就是说：

test[1]与*(test+1)等价

test[1][2]与((test+1)+2)等价

那么可知该题把rain[year][month]改为*(*(rain+year)+month)即可

ps:但是谁会用指针写法啊啊啊啊，这也太麻烦了啊啊啊啊😢

原文地址：http://www.cnblogs.com/Lemon-233/p/16853542.html