C-二维数组,多维数组

-----二维数组

->在数组定义当中,行数和列数需要用常量定义

->在定义的时候如果没有数值进行填充,则补零

->第一个数是行,第二个数是列

->行可以不写,但必须定义列

        int array [4][3] = {1,2,3,4,5,6,7,8,9,0,1,2};
        int array1[4][3] = {{11,12,13},{14,15,16},{17,18,19},{20}};

        printf("%d",array[0][0]);
        printf("\t%d",array1[3][0]);

        int a = 0 ;
        int b = 0 ;
        array[a][b] = 0;
        printf("\t%d",array[0][0]);

        int array[][4] = {1,2,3,4,5,6,7,8,9};

        int array[][4] = {1,2,3,4,5,6,7,8,9};
        printf("%lu",sizeof(array));

        int array[][4] = {1,2,3,4,5,6,7,8,9};
       // printf("%lu",sizeof(array));

        for (int i = 0; i < 3; i ++) {
            for (int j = 0; j < 4; j++) {
                printf("%d ",array[i][j]);
            }
            printf("\n");
        }

->所占用的内存空间

        int array[][4] = {1,2,3,4,5,6,7,8,9};
        printf("%lu",sizeof(array));

        int array[][4] = {1,2,3,4,5,6,7,8,9};
        printf("%lu",sizeof(array));

->二维数组打印的话需要两层循环的配合,第一层代表行,第二层代表列

        int array[4][5];
        for (int i = 0; i < 4; i ++) {
            for (int j = 0; j < 5; j ++) {
                array[i][j] = arc4random() % 101;
                printf("%d\t",array[i][j]);
            }
            printf("\n");
        }
    

->数组求和练习

        int sum = 0;
        for (int i = 0; i < 4; i++) {
            sum = sum + array[0][i];

        }
        printf("\n第0行总和:%d",sum);
        int sum1 = 0    ;
        for (int i = 0; i < 3; i ++) {
            for (int j = 0; j < 4; j++) {
                sum1 =  sum1 + array[i][j];
            }
            printf("\n第%d行的总和:%d",i ,sum1);
            sum1 = 0;
        }
        printf("\n");
        int sum2 = 0;
            for (int i = 0; i < 4; i++) {
                for (int j = 0; j < 3; j++) {
                    sum2 = sum2 + array[j][i];//谁变化的快就放到内层循环
                }
                printf("\n第%d列的总和:%d",i,sum2);
                sum2 = 0;
            }

——字符串数组(字符数组)

->存储多个字符串

->char string[i][j] 可以保存i个字符串,每个字符串不能大于j-1个

第一位度表示可以放几个字符串,第二维度每个字符串表示最大长度-1;

->可以用一个下标访问,访问的是整个字符串

->两个下标访问的是字符

->不能直接替换

->得用strcpy

        char string[3][10] = {"maoyuanbo","maomao","hahahaha"};
        printf("%c",string[0][1]);
        printf("\n%s",string[1]);

        char string[3][10] = {"iphone","android","winphone"};

        printf("%c",string[0][1]);
        printf("\n%s",string[0]);
        strcpy(string[0], "nokia");
        printf("\n%s",string[0]);
    

>冒泡排序

 1         char string[5][20] = {0};
 2         for (int i = 0; i < 5; i++) {
 3             scanf("%s",string[i]);
 4         }
 5
 6         for (int i = 0; i < 4; i++) {
 7             for (int j = 0; j < 4 - i; j++) {
 8                 if (strcmp(string[j], string[j+1]) > 0) {
 9                     char name[20] = {0};
10                     strcpy(name, string[j]);
11                     strcpy(string[j], string[j+1]);
12                     strcpy(string[j+1], name);
13                 }
14             }
15         }
16         for (int i = 0; i < 5; i++) {
17             printf("\n%s",string[i]);
18         }
19     

->选择排序

 1         char string[5][20] = {0};
 2         int minindex = 0;//设最小值为第一个数
 3         for (int i = 0; i < 5; i++) {
 4             scanf("%s",string[i]);
 5         }
 6         for (int i = 0; i < 4; i++) {
 7             for (int j = i + 1; j < 5; j++) {
 8                 if (strcmp(string[minindex], string[j]) > 0) {
 9                     minindex = j;
10                 }
11
12             }
13             if (minindex != i) {
14                 char name[20] = {0};
15                 strcpy(name, string[i]);
16                 strcpy(string[i], string[minindex]);
17                 strcpy(string[minindex], name);
18             }
19         }
20         for (int i = 0; i < 5; i++) {
21             printf("\n%s",string[i]);
22         }
23     

->求最大字符串长度

 1         char string[5][20] = {0};
 2         unsigned long maxworld = 0;//定义一个最大的字符串长度
 3         for (int i = 0; i < 5; i++) {
 4             scanf("%s",string[i]);
 5         }
 6         //求出最长长度
 7         for (int i = 0; i < 5; i++) {
 8             if (strlen(string[i]) > maxworld) {
 9                 maxworld =  strlen(string[i]);
10             }
11         }
12         printf("最长长度为:%ld\n",maxworld);
13         for (int i = 0; i < 5; i++) {
14             if (strlen(string[i]) == maxworld) {
15                 printf("%s\t",string[i]);
16             }
17         }
18
19
20         char array[5][20] = {0};
21         unsigned long maxworld = 0;
22         for (int i = 0; i < 5; i++) {
23             scanf("%s",array[i]);
24         }
25         for (int i = 0; i < 5; i++) {
26             if (strlen(array[i]) > maxworld) {
27                 maxworld = strlen(array[i]);
28             }
29         }
30         printf("最长长度:%ld\n",maxworld);
31         for (int i = 0; i < 5; i ++) {
32             if (strlen(array[i]) == maxworld) {
33                 printf("%s  ",array[i]);
34             }
35         }
36         

——多维数组

    int a[2][2][2] = {0};
    int sum = 0,sum1 = 0;
    for (int i = 0; i < 2; i ++) {
        for (int j = 0; j < 2; j ++) {
            for (int k = 0; k < 2; k++) {
                a[i][j][k] = arc4random() % 11;
                printf("%d\t",a[i][j][k]);
                sum1 =a[i][j][k] +sum1;
                sum = a[i][j][k] +sum;
            }
            printf("每一行总和:%d",sum1);
            sum1 = 0;
            printf("\n");
        }
        printf("每一层总和:%d",sum);
        sum = 0;
        printf("\n\n");
    }