c - 使用指针传递 2D 数组 (C)

Question

下面是我正在使用的代码。当我运行它并注释掉处理 addArray 函数的代码时，效果非常好。

我相信我没有在 addArrays 函数中正确使用指针。任何帮助将不胜感激。

#include <stdio.h>
#include <stdlib.h>
#include <time.h>

void addArrays(int rowSize, int columnSize, int Array1[rowSize][columnSize],
               int Array2[rowSize][columnSize],
               int *sumloc[rowSize][columnSize]);
void printArray(int rowSize, int columnSize, int arrayValue[rowSize][columnSize]);

/*
This program will make 2 2D matrices out of a random number of rows, 3 columns, and a random set of values.
Then, the two matrices will be added and all three printed.
*/

int main() {
    //To get a true random number
    srand(time(NULL));

    int rowSize = rand() % 4 + 1;
    int columnSize = 2;
    int Array1[rowSize][columnSize];
    int Array2[rowSize][columnSize];
    int Arraysum[rowSize][columnSize];

    //For loop counter
    int col;
    int row;

    //Makes a unique number for each part of both arrays from 0-50
    for (row = 0; row <= rowSize; row++)
        for (col = 0; col <= columnSize; col++)
            Array1[row][col] = rand() % 50;

    for (row = 0; row <= rowSize; row++)
        for (col = 0; col <= columnSize; col++)
            Array2[row][col] = rand() % 50;


    //Add arrays
    addArrays(rowSize, columnSize, Array1[rowSize][columnSize],
              Array2[rowSize][columnSize],v&Arraysum[rowSize][columnSize]);

    //Utilizes the print function
    printArray(rowSize, columnSize, Array1);
    printArray(rowSize, columnSize, Array2);
    printArray(rowSize, columnSize, &Arraysum);

    return 0;
}

void addArrays(int rowSize, int columnSize, int a1[rowSize][columnSize],
               int a2[rowSize][columnSize],
               int *sumloc[rowSize][columnSize]) {
    int row;
    int col;
    sumloc[rowSize][columnSize] = malloc(rowSize * columnSize * sizeof(int));

    for (row = 0; row <= rowSize; row++)
        for (col = 0; col <= columnSize; col++)
            *sumloc[row][col] = a1[row][col] + a2[row][col];

    return;
}

void printArray(int rowSize, int columnSize, int arrayValue[rowSize][columnSize]) {
    int row;
    int col;

    for (row = 0; row <= rowSize; row++) {
        printf("\n");
        printf("[");
        for (col = 0; col <= columnSize; col++) {
            printf(" %d ", arrayValue[row][col]);
        }
        printf("]");
    }
    printf("\n\n");

    return;
}

Answer 1

您的代码有几个问题:

• 您不应该使用<=在你的for循环时，您可以访问数组末尾之外的元素。
• 行数和列数均为一。
• 您应该直接传递数组，而不是传递数组元素或暂时传递目标数组的地址。

这是更正后的版本:

#include <stdio.h>
#include <stdlib.h>
#include <time.h>

void addArrays(int rowSize, int columnSize, int Array1[rowSize][columnSize],
               int Array2[rowSize][columnSize],
               int Result[rowSize][columnSize]);
void printArray(int rowSize, int columnSize, int arrayValue[rowSize][columnSize]);

/*
This program will make 2 2D matrices out of a random number of rows
and 3 columns, and a random set of values.
Then, the two matrices will be added and all three printed.
*/

int main() {
    //To get a pseudo random number
    srand(time(NULL));

    int rowSize = rand() % 4 + 1;  // number between 1 and 4
    int columnSize = 3;
    int Array1[rowSize][columnSize];
    int Array2[rowSize][columnSize];
    int Arraysum[rowSize][columnSize];

    //Makes a unique number for each part of both arrays from 0-50
    for (int row = 0; row < rowSize; row++) {
        for (int col = 0; col < columnSize; col++) {
            Array1[row][col] = rand() % 50;
            Array2[row][col] = rand() % 50;
        }
    }

    //Add matrices
    addArrays(rowSize, columnSize, Array1, Array2, Arraysum);

    //Utilizes the print function
    printArray(rowSize, columnSize, Array1);
    printArray(rowSize, columnSize, Array2);
    printArray(rowSize, columnSize, Arraysum);
    return 0;
}

void addArrays(int rowSize, int columnSize, int a1[rowSize][columnSize],
               int a2[rowSize][columnSize], int result[rowSize][columnSize]) {
    for (int row = 0; row < rowSize; row++) {
        for (int col = 0; col < columnSize; col++)
            result[row][col] = a1[row][col] + a2[row][col];
    }
}

void printArray(int rowSize, int columnSize, int array[rowSize][columnSize]) {
    for (int row = 0; row < rowSize; row++) {
        printf("\n");
        printf("[");
        for (int col = 0; col < columnSize; col++) {
            printf(" %d ", array[row][col]);
        }
        printf("]");
    }
    printf("\n\n");
}