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1. Multiple-Subscripted Arrays
• Example
• int a[3][4];
Row 0
Row 1
Row 2
Column 0 Column 1 Column 2 Column 3
a[ 0 ][ 0 ]
a[ 1 ][ 0 ]
a[ 2 ][ 0 ]
a[ 0 ][ 1 ]
a[ 1 ][ 1 ]
a[ 2 ][ 1 ]
a[ 0 ][ 2 ]
a[ 1 ][ 2 ]
a[ 2 ][ 2 ]
a[ 0 ][ 3 ]
a[ 1 ][ 3 ]
a[ 2 ][ 3 ]
Row subscript
Array name
Column subscript

2. Multiple-Subscripted Arrays’ Definition
type-name array-name[row-number][column-number];
• Example
int a[3][3], b[30][3];
char name[30][20];
float score[30][5];
a[3][3]
a[0] a[0][0] a[0][1] a[0][2]
a[1] a[1][0] a[1][1] a[1][2]
a[2] a[2][0] a[2][1] a[2][2]

3. Multiple-Subscripted Arrays’ Storage
• Example
• int a[2][3];
a[0][0] a[0][1] a[0][2]
a[1][0] a[1][1] a[1][2]
12
32
-1
87
0
53
a[0][0]
a[0][1]
a[0][2]
a[1][0]
a[1][1]
a[1][2]
a

4. Multiple-Subscripted Arrays’ Initialization
int a[2][3]={{10,11,12},{13,14,15}};
int a[2][3]={10,11,12,13,14,15};
a[0][0] a[0][1] a[0][2]
10 11 12
a[1][0] a[1][1] a[1][2]
13 14 15

5. Multiple-Subscripted Arrays’ Initialization
int a[2][3]={{10,11},{13}};
a[0][0] a[0][1] a[0][2]
10 11 0
a[1][0] a[1][1] a[1][2]
13 0 0
int a[2][3]={10,11,13};
a[0][0] a[0][1] a[0][2]
10 11 13
a[1][0] a[1][1] a[1][2]
0 0 0

6. Multiple-Subscripted Arrays’ Initialization
int a[ ][3]={{10,11,12},{13,14,15}};
int a[ ][3]={10,11,12,13,14,15};
a[0][0] a[0][1] a[0][2]
10 11 12
a[1][0] a[1][1] a[1][2]
13 14 15

7. Multiple-Subscripted Arrays’ Initialization
int a[ ][3]={{10,11},{13}};
a[0][0] a[0][1] a[0][2]
10 11 0
a[1][0] a[1][1] a[1][2]
13 0 0

8. Examples: Multiple-Subscripted Arrays
Example: Multiple-Subscripted Arrays







6
5
4
3
2
1
a











6
3
5
2
4
1
b
for(i=0;i<3;i++)
for(j=0;j<2;j++)
b[i][j] = a[j][i]

9. Examples: Multiple-Subscripted Arrays
Example: Multiple-Subscripted Arrays
#include <stdio.h>
void main() {
int a[2][3]={1,2,3,4,5,6}, b[3][2];
int i, j;
printf("matrix a is:n");
for (i=0; i<2; i++) {
for (j=0; j<3; j++) {
b[j][i] = a[i][j];
printf("%3d", a[i][j]);
}
printf("n");
}

10. Examples: Multiple-Subscripted Arrays
Example: Multiple-Subscripted Arrays
printf("matrix b is:n");
for (i=0; i<3; i++) {
for (j=0; j<2; j++)
printf("%3d", b[i][j]);
printf("n");
}
}
matrix a is:
1 2 3
4 5 6
matrix b is:
1 4
2 5
3 6

11. Examples: Multiple-Subscripted Arrays
Example: Multiple-Subscripted Arrays










3
5
7
9
6
8
5
7
4
3
2
1

12. Examples: Multiple-Subscripted Arrays
Example: Multiple-Subscripted Arrays
……
for (i=0; i<3; i++)
for (j=3; j>0; j--)
if (num[i][j]>num[i][j-1]) {
tmp = num[i][j];
num[i][j] = num[i][j-1];
num[i][j-1] = tmp;
}
……