C语言多维数组的实现与操作

标签：dim va int bounds C语言 ap 数组 多维 constants

常量和所需的头文件

#include<stdio.h>
#include<stdarg.h>
#include<stdlib.h>
#define MAX_ARRAY_DIM 8 //设置数组维数最大为8
#define ElemType int
#define ERROR -1
#define SUCCESS 1
#define OVERFLOW -2
#define UNDERFLOW -3

结构体

typedef struct {
	ElemType* base;//数组元素基址，由InitArray分配
	int dim;//数组维数
	int* bounds;//数组维界基址，由InitArray分配
	int* constants;//数组映像函数常量基址，由InitArray分配
}Array;

构造数组A

Array InitArray(Array A, int dim, ...) {
	//若维数dim和各维长度合法，则构造相应的数组A
	if (dim<1 || dim>MAX_ARRAY_DIM)
	{
		exit(ERROR);
	}
	A.dim = dim;
	A.bounds = (int*)malloc(dim * sizeof(int));
	if (!A.bounds)
	{
		exit(OVERFLOW);
	}
	//若各维长度合法，则存入A.bounds,并求出A的元素总数elemtotal
	int elemtotal = 1;
	va_list ap;
	va_start(ap, dim);
	for (int i = 0; i < dim; i++)
	{
		A.bounds[i] = va_arg(ap, int);
		if (A.bounds[i] < 0)
		{
			exit(UNDERFLOW);
		}
		elemtotal *= A.bounds[i];
	}
	va_end(ap);
	A.base = (ElemType*)malloc(elemtotal * sizeof(ElemType));
	if (!A.base)
	{
		exit(OVERFLOW);
	}
	//求映像函数的常数ci，并存入A.constants[i-1],i=1,...,dim
	A.constants = (int*)malloc(elemtotal * sizeof(ElemType));
	if (!A.base)
	{
		exit(OVERFLOW);
	}
	A.constants[dim - 1] = 1;//L=1,指针的增减以元素的大小为单位
	for (int i = dim - 2; i >= 0; i--)
	{
		A.constants[i] = A.bounds[i + 1] * A.constants[i + 1];
	}
	return A;
}

销毁释放数组

Array DestoryArray(Array A) {
	if (!A.base)
	{
		exit(ERROR);
	}
	free(A.base);
	A.base = NULL;
	if (!A.bounds)
	{
		exit(ERROR);
	}
	free(A.bounds);
	A.bounds = NULL;
	if (!A.constants)
	{
		exit(ERROR);
	}
	free(A.bounds);
	A.bounds = NULL;
	return A;
}

求出元素在数组中的相对地址

int Locate(Array A, va_list ap, int off) {
	//若ap指示的各下标值合法，则求出该元素在A中相对地址off
	for (int i = 0; i < A.dim; i++)
	{
		int ind = va_arg(ap, int);
		if (ind < 0 || ind >= A.bounds[i]) {
			exit(OVERFLOW);
		}
		off += A.constants[i] + ind;
	}
	return off;
}

获取A相应位置值函数

int Value(Array A, ElemType e, ...) {
	//A是N维数组，e为元素变量，随后是n个下标值
		//若下标不超界，则e赋值为所指定的A的元素值
	va_list ap;
	int off = 0;
	va_start(ap, e);
	if ((Locate(A, ap, off)) <= 0)
	{
		exit(ERROR);
	}
	e = *(A.base + off);
	return e;
}

为A指定位置赋值函数

Array Assign(Array A, ElemType e, ...) {
	//A是n维数组，e是元素变量，随后是n个下标值
	//若下标不超界，则将e值赋给所指定的A的元素
	va_list ap;
	int off = 0;
	va_start(ap, e);
	if (Locate(A, ap, off) <= 0)
	{
		exit(ERROR);
	}
	*(A.base + off) = e;
	return A;
}

main函数调用

int main(void) {
	int off = 0;
	Array A = { NULL,0,NULL,NULL };
	ElemType arrayB[4][3] = { {1,2,3},{4,5,6},{7,8,9},{10,11,12} };
	int dim = 2, bounds = 4, constants = 3, e = 0;
	A = InitArray(A, dim, bounds, constants);
	for (int i = 0; i < bounds; i++)
	{
		for (int j = 0; j < constants; j++) {
			Assign(A, arrayB[i][j], i, j);
			printf("value=%d\n", Value(A, e, i, j));
		}
	}
	printf("A.dim=%d\n", A.dim);

	A = DestoryArray(A);
	printf("A.base=%p\n", A.base);
}

标签：dim,va,int,bounds,C语言,ap,数组,多维,constants
From： https://www.cnblogs.com/homeskating/p/17156621.html