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

int main(void){
    int r1, c1, r2, c2, r3, c3;
    int r, c, aux;
    float **m1, **m2, **m3;
    float sum;

    do{
        do{
          printf("Rows for Matrix M: ");
          scanf("%d", &r1);
          printf("Columns for Matrix M:");
          scanf("%d", &c1);
            if(r1 < 1 || c1 < 1)
            printf("Invalid dimensions for Matrix M. Type again.\n");
        }while(r1 < 1 || c1 < 1);

        do{
          printf("Rows for Matrix m: ");
          scanf("%d", &r2);
          printf("Columns for Matrix m:");
          scanf("%d", &c2);
            if(r2 < 1 || c2 < 1)
            printf("Invalid dimensions for Matrix m. Type again.\n");
        }while(r2 < 1 || c2 < 1);

        if(c1!=r2)
        printf("\nError! Rows for M1 and Columns for M2 must match.\n");

    }while(c1!=r2);

    r3 = r1;
    c3 = c2;

    if((m1 = (float **) malloc(r1*sizeof(float *)))==NULL){
        printf("\nInsufficient Memory.");
        exit(1);
    }

    for(r = 0; r < r1; r++){
    if((*(m1+r) = (float *) malloc(c1*sizeof(float)))==NULL){
    printf("\nInsufficient Memory.");
        exit(1);
    }

    if((m2 = (float **) malloc(r2*sizeof(float *)))==NULL){
        printf("\nInsufficient Memory.");
        exit(1);
    }

    for(r = 0; r < r2; r++){
    if((*(m2+r) = (float *) malloc(c2*sizeof(float)))==NULL){
    printf("\nInsufficient Memory.");
        exit(1);
    }

    if((m3 = (float **) calloc(r3,sizeof(float *)))==NULL){
        printf("\nInsufficient Memory.");
        exit(1);
    }

    for(r = 0; r < r3; r++){
    if((*(m2+r) = (float *) calloc(c3,sizeof(float)))==NULL){
    printf("\nInsufficient Memory.");
        exit(1);
    }

    for(r = 0; r < r1; r++){
        for(c = 0; c < c1; c++){
            printf("M[%d][%d]: ", r, c);
            scanf("%f", *(m1+r)+c);
    }
    printf("\n");
    }

    for(r = 0; r < r2; r++){
        for(c = 0; c < c2; c++){
            printf("m[%d][%d]: ", r, c);
            scanf("%f", *(m2+r)+c);
    }
    printf("\n");
    }

    for(r = 0; r < r3; r++){
        for(c = 0; c < c3; c++){
    *(m3+(c3.r+c)) += (*m1+(c1.r+c))*(*m2+(c2.r+c));