1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
|
#include <stdio.h>
#include <stdlib.h>
#define ROWS 6
#define COLUMNS 5
#define P(a) \
{ \
printf("sizeof(%s):\t%d\n",#a, (sizeof((a)))); \
printf("sizeof(%s[0]):\t%d\n",#a,(sizeof((a)[0]))); \
}
#define OUT(a) \
{ \
printf("%s:\t addr:%p\n",(#a),(a)); \
for(int i = 0; i < ROWS; i++){ \
printf("%s[%d]:\t addr:%p\n",#a,i,((a)[i])); \
} \
for(int i = 0; i < ROWS; i++){ \
for(int j = 0; j < COLUMNS; j++){ \
printf("%s[%d][%d]: addr:%p\t",(#a),i,j,&a[i][j]);\
} \
printf("\n"); \
} \
}
#define INFO(a) \
{ \
P(a) \
OUT(a) \
}
int main(int argc, char *argv[])
{
printf("-----二维数组-----\n");
printf("a[%d][%d]\n",ROWS,COLUMNS);
char (*a1)[COLUMNS];
a1 = (char(*)[COLUMNS])calloc(ROWS,sizeof(char*));
printf("*****数组指针*****\n");
INFO(a1)
char *a2[ROWS];
for(int i = 0; i < ROWS; i++) {
a2[i] = (char*)calloc(COLUMNS, sizeof(char));
}
printf("*****指针数组*****\n");
INFO(a2)
char *a3[ROWS];
a3[0] = (char *)calloc(ROWS*COLUMNS, sizeof(char));
for(int i = 1; i < ROWS; i++) {
a3[i] = a3[i-1] + COLUMNS;
}
printf("*****指针数组，一次分配内存*****\n");
INFO(a3)
char **a4;
a4 = (char **)calloc(ROWS, sizeof(char*));
for(int i = 0; i < ROWS; i++) {
a4[i] = (char*)calloc(COLUMNS, sizeof(char));
}
printf("*****两维都未知*****\n");
INFO(a4)
char **a5;
a5 = (char**)calloc(ROWS, sizeof(char*));
a5[0] = (char*)calloc(ROWS*COLUMNS, sizeof(char));
for(int i = 1; i < ROWS; i++) {
a5[i] = a5[i-1] + COLUMNS;
}
printf("*****两维都未知，一次分配内存*****\n");
INFO(a5)
free(a1);
for(int i = 0; i < ROWS; i++) {
free(a2[i]);
}
free(a3[0]);
for(int i = 0; i < ROWS; i++) {
free(a4[i]);
}
free(a4);
free(a5[0]);
free(a5);
return 0;
}
|