c - 为什么我的函数没有真正初始化数组？

Question

我正在尝试编写一个将数组初始化为零的函数:

void InitializingToZero(int numOfrows, int numOfcols, int array[][20]) {
    for (int i = 0; i < numOfrows; i++) {
        for (int j = 0; j < numOfcols; j++) {
            array[i][j] = 0;
        }
    }
}

int main() {
    int num_of_rows = 3;    
    int num_of_cols = 3;

    int array[num_of_rows][num_of_cols];

    InitializingToZero(num_of_rows, num_of_cols, array);

    for (int i = 0; i < num_of_rows; i++) {
        for (int j = 0; j < num_of_cols; j++) {
            printf("%d ", array[i][j]);
        }
        printf("\n");
    }
}

我得到这个输出:

0 0 0
0 0 0
268501009 0 4200656

Answer 1

错误是

int num_of_rows = 3;    
int num_of_cols = 3;

然后您传递列字段为 20 的数组。因此，数组未正确初始化。这就是问题所在。

你应该这样做

void InitializingToZero(int numOfrows, int numOfcols, int array[][numOfcols]) {

how can i do it if just know that the max size of the array it's can be 20x20, and the numOfrows, numOfcols are inputs from the user?

然后你这样做

#define MAXSIZE 20

int array[MAXSIZE ][MAXSIZE];

..


InitializingToZero(num_of_rows, num_of_cols, array);

函数是

void InitializingToZero(int numOfrows, int numOfcols, int array[][MAXSIZE]) {