C 中的矩阵乘法 - 输入问题

Question

我编写了一个使用函数执行矩阵乘法的程序。代码如下：

#include <stdio.h>
void obtainMatrixElems(int mtrx[][10], int row_elems, int column_elems);
void multMatrixes(int matrix1[][10], int matrix2[][10], int multAns[][10], int rowmat1, int rowmat2, int colmat1, int colmat2);
void resDisp(int multAns[][10], int row_elems, int col_elems);

int main() {
    int rowmat1, rowmat2, colmat1, colmat2, matrix1[10][10], matrix2[10][10], multAns[10][10];

    printf("Kindly enter the number of row/s for the first matrix: \n");
    scanf("%d", &rowmat1);
    printf("Kindly enter the number of column/s for the first matrix: \n");
    scanf("%d", &colmat1);
    printf("Kindly enter the number of row/s for the first matrix: \n");
    scanf("%d", &rowmat2);
    printf("Kindly enter the number of column/s for the second matrix: \n");
    scanf("%d", &colmat2);

    while(colmat1 != rowmat2){
        printf("This matrix is not computable. Kindly re-enter the correct data.\n");
        printf("Number of row/s for the first matrix: \n");
        scanf("%d", &rowmat1);
        printf("Number of column/s for the first matrix: \n");
        scanf("%d", &colmat1);
        printf("Number of row/s for the second matrix: \n");
        scanf("%d", &rowmat2);
        printf("Number of column/s for the second matrix: \n");
        scanf("%d", &colmat2);
    }

    //calling defined function which will obtain elements of the matrix - function is called for both matrices independantly
    obtainMatrixElems(matrix1, rowmat1, colmat1); //matrix 1
    obtainMatrixElems(matrix2, colmat2, rowmat2); //matrix 2

    //calling defined function which will compute multiplication of the two matrices.
    multMatrixes(matrix1, matrix2, multAns, rowmat1, colmat1, rowmat2, colmat2);

    //calling defined function in order to display resultant matrix.
    resDisp(multAns, rowmat1, colmat2);
}
//defining function which will be used in order to obtain the elements of a matrix
void obtainMatrixElems(int mtrx[][10], int row_elems, int col_elems){
    printf("Kindly enter matrix elements: \n");

    for(int x = 0; x < row_elems; x++){
        for(int y = 0; y < col_elems; y++){
            printf("Enter element at position %d,%d: \n", x+1, y+1);
            scanf("&d", &mtrx[x][y]);
        }
    }
}

//defining function which will be used in order to multiply the matrixes together.
void multMatrixes(int matrix1[][10], int matrix2[][10], int multAns[][10], int rowmat1, int rowmat2, int colmat1, int colmat2){

    //making matrix multiplication result equal to 0 for initialization purposes
    for(int x = 0; x < rowmat1; x++){
        for(int y = 0; y < colmat2; y++){
            multAns[x][y] = 0;
        }
    }

    //mutliplying the matrices

    for(int x = 0; x < rowmat1; x++){
        for(int y = 0; y < colmat2; y++){
            for(int z = 0; z < colmat1; z++){
                multAns[x][y] = matrix1[x][y] * matrix2[x][y];
            }
        }
    }
}

//defining function which will be used in order to display the resultant matrix
void resDisp(int multAns[][10], int row_elems, int col_elems){
    printf("\nRESULTANT MATRIX:\n");
    for (int x = 0; x < row_elems; ++x) {
        for (int y = 0; y < col_elems; ++y) {
            printf("%d", multAns[x][y]);
            if (y == col_elems - 1)
                printf("\n");
        }
    }
}

但是，当我运行该程序时，会遇到以下输出：

Kindly enter the number of row/s for the first matrix: 
3
Kindly enter the number of column/s for the first matrix: 
3
Kindly enter the number of row/s for the first matrix: 
3
Kindly enter the number of column/s for the second matrix: 
3
Kindly enter matrix elements: 
Enter element at position 1,1: 
Enter element at position 1,2: 
Enter element at position 1,3: 
Enter element at position 2,1: 
Enter element at position 2,2: 
Enter element at position 2,3: 
Enter element at position 3,1: 
Enter element at position 3,2: 
Enter element at position 3,3: 
Kindly enter matrix elements: 
Enter element at position 1,1: 
Enter element at position 1,2: 
Enter element at position 1,3: 
Enter element at position 2,1: 
Enter element at position 2,2: 
Enter element at position 2,3: 
Enter element at position 3,1: 
Enter element at position 3,2: 
Enter element at position 3,3: 

RESULTANT MATRIX:
000
000
000

Process finished with exit code 0

函数 obtainMatrixElems 中的循环似乎有问题——尽管我可能是错的。我完全不知道它可能是什么，所以任何帮助将不胜感激。

尝试使用函数在 C 中执行矩阵乘法 - 获得矩阵元素的函数循环两次并且不排除任何输入。程序在代码 0 之后终止。

Answer 1

您对scanf的调用有误 它应该读作

scanf("%d", &mtrx[x][y]);

还要注意在每次输入后按 Enter 键。为了安全起见，你应该抓住它。使用类似的东西

scanf(" %d", &mtrx[x][x]);

Answer 2

您似乎在multAns[x][y] = matrix1[x][y] * matrix2[x][y]; 缺少一个“+”。

它应该是：

multAns[x][y] += matrix1[x][y] * matrix2[x][y];

如果你最后的操作结果是0 那么这就解释了为什么你得到一个 0 矩阵..

编辑：

标志是问题之一。您从用户那里获得输入的方式也有问题。

    for(int x = 0; x < row_elems; x++){
        for(int y = 0; y < col_elems; y++){
            printf("Enter element at position %d,%d: 
", x+1, y+1);
            // Note the change of "&" to "%" and the extra sequence
            // "
" which expects the user to press ENTER (i.e.:
            // new line) between input cells
            scanf("%d
", &mtrx[x][y]);
        }
    }