用c ++将矩阵/ 2d数组复制到另一个数组

I am trying to copy a 2d array into another 2d array, i have these two array created:

我试图将2d数组复制到另一个2d数组中,我创建了这两个数组:

#define mapXcor 50
#define mapYcor 50

char secondStage    [mapXcor][mapYcor];
char currentStage   [mapXcor][mapYcor];
//mapXcor and mapYcor are constant integers

Now my secondStage[][] array is populated with values on it, but currentStage[][] isn't, and i want to assign the values of secondStage to currentStage. So i created the function bellow:

现在我的secondStage [] []数组中填充了值,但currentStage [] []不是,我想将secondStage的值赋给currentStage。所以我创建了以下函数:

void populateArray(char (&arrayA)[mapXcor][mapYcor], char arrayB[mapXcor][mapYcor]) {
    for(int a = 0; a < mapXcor + 1; ++a) {
        for(int b = 0; b < mapYcor + 1; ++b) {
            arrayA[mapXcor][mapYcor] = arrayB[mapXcor][mapYcor];
        }
    }
}

populateArray(currentStage[mapXcor][mapYcor],secondStage[mapXcor][mapYcor]);

But when i use the function it gives me a error :

但是,当我使用该功能时,它给了我一个错误:

1 IntelliSense: a reference of type "char (&)[20][50]" (not const-qualified) cannot be initialized with a value of type "char"

1智能感知:类型为“char(&)[20] [50]”的参考(非const限定)无法使用“char”类型的值进行初始化

2 IntelliSense: argument of type "char" is incompatible with parameter of type "char (*)[50]"

2 IntelliSense:“char”类型的参数与“char(*)[50]”类型的参数不兼容

How could I fix this?

我怎么能解决这个问题?

3 个解决方案

#1

change the assignment sentence in your for-loop:

更改for循环中的赋值语句:

arrayA[mapXcor][mapYcor] = arrayB[mapXcor][mapYcor];

arrayA[a][b] = arrayB[a][b];

#2

Code you probably are trying to reach. Do not show it to teacher :-) - there is too much from practical programming. Just look and then write your own solutions:

您可能想要达到的代码。不要向老师展示:-) - 实际编程太多了。只需查看然后编写自己的解决方案:

#include <string.h>
#include <stdio.h>

#define mapXcor 5
#define mapYcor 5

static char secondStage    [mapXcor][mapYcor];
static char currentStage   [mapXcor][mapYcor];

void populateArray(char (&arrayA)[mapXcor][mapYcor], const char (&arrayB)[mapXcor][mapYcor]) {
/*
    for(int a = 0; a < mapXcor; ++a) {
        for(int b = 0; b < mapYcor; ++b) {
            arrayA[a][b] = arrayB[a][b];
        }
    }
*/
    memcpy(arrayA, arrayB, sizeof(arrayB));
}

int main()
{
    for(int a = 0; a < mapXcor; ++a) {
        for(int b = 0; b < mapYcor; ++b){
            currentStage[a][b] = a*b + 10*a;
        }
    }

    populateArray(secondStage, currentStage);

    for(int a = 0; a < mapXcor; ++a) {
        for(int b = 0; b < mapYcor; ++b){
            printf("%2i ", secondStage[a][b]);
        }
        printf("\n");
    }

    return 0;
}

Comments:

You have bad array index limits in cycle. Look for corrected function under comment.

循环中的数组索引限制很差。在评论下寻找纠正的功能。

You have wrong indexes in assignment in cycle. Again, commented out code.

循环中的赋值有错误的索引。再次,注释掉了代码。

If you passed one array by reference (destination) why not to use constant reference for source?

如果您通过引用(目标)传递一个数组,为什么不对源使用常量引用?

In practice as your areas have the same type (you could even define them as having the same type) nobody copies them by elements. I have used memcpy() but this is only good if memory areas do not overlap (in this case - yes). check man 3 memcpy.

实际上,由于您的区域具有相同的类型(您甚至可以将它们定义为具有相同类型),因此没有人按元素复制它们。我已经使用了memcpy(),但只有当内存区域不重叠时才这样做(在这种情况下是 - 是)。检查男人3 memcpy。

Learn harder :-)

学习更难:-)

#3

#define ROWS 2
#define COLS 2

void copyArray(char (&arrayA)[ROWS][COLS], const char (&arrayB)[ROWS][COLS] ) {

    memcpy(arrayA, arrayB, sizeof(arrayB));
}

int main(void){

    char arr1  [ROWS][COLS];
    char arr2  [ROWS][COLS];

    // init arr1
    copyArray(arr2, arr1);

    return 0;
}

#1