Matrix Multiplication Issues in C - c

Question

I'm making a matrix multiplication calculator in C. When I run it, spews out many numbers and results in this:
57736 segmentation fault
Where did I write wrong? Here is the code I wrote:
int Mtx1row, Mtx1col, Mtx2row, Mtx2col, c, d, e;
int first[10][10], second[10][10], mult[10][10];
Get 1st Matrix row and col
printf("First Matrix: # of row and col?\n");
scanf("%d%d", &Mtx1row, &Mtx1col);
Get 2nd Matrix row and col
printf("Second Matrix: # of row and col?\n");
scanf("%d%d", &Mtx2row, &Mtx2col);
Compare 1st Matrix col vs 2nd Matrix row
if (Mtx1col != Mtx2row){
printf("Mtx1col != Mtx2row (x _ x)\n");
return 1;
}
Get elements of first matrix
printf("Enter elements of First Matrix: \n");
for (c = 0; c < Mtx1row; c++)
for (d = 0; d < Mtx1col; d++)
{
printf("\tEnter element %d%d: ", c+1, d+1);
scanf("%d", &first[c][d]);
}
Get elements of second matrix
printf("Enter elements of Second Matrix: \n");
for (c = 0; c < Mtx2row; c++)
for (d = 0; d < Mtx2col; d++)
{
printf("\tEnter element %d%d: ", c+1, d+1);
scanf("%d", &second[c][d]);
}
Multiply Matrix 1 and 2 and store into Matrix Product
for (c=0; c < Mtx2row; c++){
for (d=0; d < Mtx2col; d++){
for (e=0; e < Mtx1col; e++){
mult[c][d] += first[c][d] * second[d][e];
}
}
}

Answer 1

Two matrices could be multiplied if an only if
#columns of the first matrix = #rows of the second matrix.
So you need to check this before creating the 2D arrays themselves.
if(Mtx1col == Mtx2row){
//proceed creating the matrices
int first[Mtx1row][Mtx1col], second[Mtx2row][Mtx2col];
int mult[Mtx1row][Mtx2col]; // The resulting matrix is Mtx1row * Mtx2col
// You have variable length arrays(VLAs) above.
}
else{
// put the f/b code here
}
Note
Under C11, VLAs are an optional feature rather than a mandatory feature,
as they were under C99.
The term variable in variable-length array does not mean that you can
modify the length of the array after you create it. Once created, a
VLA keeps the same size. What the term variable does mean is that you
can use a variable when specifying the array dimensions when first
creating the array.
The above excerpt is from Stephen Prata's C++ Primer Plus 6th edition

Answer 2

At least one of your array variables mult, first, second does not provide enough memory for the accesses happening.
When Mtx2row, Mtx2col and Mtx1col have values between 0 and 10 inclusively, the memory accesses should be fine. So please check the value of these variables. As a first step you can just printf these values, better would be a programmatic check that precludes out of bounds values. Also, please check that the matrices have compatible dimensions for matrix multiplication, i.e. Mtx1col must be equal to Mtx2row.
EDIT:
Now that the shown code includes the scanf statements, I can give the following advice. Always check the return code of scanf to ensure all arguments have been parsed. You can even add an additional %c to ensure there was no extra input. In your case you also have to check if the read array indices are inside the permissible range (here 0-9).