Matrix Multiplication in C - Problem with inputs-CodePudding

I've written a program which carries out matrix multiplication using functions. The function which i presume is wrong is as follows:

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]);
        }
    }
}

When I run the program, I am met with this output:

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

There seems to be a problem with the loop in function obtainMatrixElems - although I could be wrong. I'm quite lost as to what it may be so any help would be greatly appreciated.

Tried carrying out matrix multiplication in C using functions - function which obtains matrix elements loops twice and does not except any inputs. Program terminates after with code 0.

CodePudding user response：

There is an error in your call to scanf It should read

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

Also take care with hitting the Enter Key after each input. To be safe you should catch it. Use something like

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

CodePudding user response：

It seems you are missing a " " at multAns[x][y] = matrix1[x][y] * matrix2[x][y];.

It should rather be:

// Also note the change variables used for referencing cells ...
multAns[x][y]  = matrix1[x][z] * matrix2[z][y];

In case your last operation result is 0 then this explains why you get a 0 matrix..

EDIT:

The sign is one of the problems .. There is also something wrong with the way you get input from the user.

    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);
            // Note the change of "&" to "%" and the extra sequence
            // "\r\n" which expects the user to press ENTER (i.e.:
            // new line) between input cells
            rc = scanf("%d\r\n", &mtrx[x][y]);
            if (rc != 1) {
                printf("ERROR: scanf did not proceed as expected\r\n");
            }
        }
    }