Doubt about matrix values

Question

A good example of a data set is booking a flight tickets. Build a C program for booking plane tickets. The plane has 50 rows with 6 seats each. The program must have:

• Two vectors whose number of positions is the total number of seats of the aeroplane.

• In one vector will be registered the name of the passenger of each seat and in the other, the number of the seat.

• A matrix to represent each seat. If the seat is occupied, the value 1 (one) will be stored in the matrix position. If the seat is free, the value 0 (zero).

Initialize all array positions to 0 (zero ).

#include <stdio.h>
#include<string.h>


main () {


int assentos[300] ; //Vetor com número de assentos
char nomes[300][15] ; //Matriz para os nomes de cada passageiro 

int contadorAssentos = 0 ; //Variável de acesso ao índice do vetor assentos
int contadorNomes = 0 ; //Variável de acesso a matriz nomes 

int ocupados[50][6]  ;  //Matriz para cada assento
char escolha ; //Variável de escolha para prosseguir com o programa ou não
int i,j ; //Variável de controle da matriz de assentos



// Preenchendo e imprimindo a matriz de assentos ocupados ou não com zero para verificação
for ( i = 0 ; i <= 49; i++)  {


            for (j = 0 ; j <= 5 ; j++) {


                        ocupados[i][j] = 0 ;

                        printf ("%d", ocupados[i][j]) ;

                        }
    printf ("\n");
}



//Fim loop de preenchimento



//Inicia programa
do { 



printf ("\nDigite o nome do passageiro : ") ;
scanf("%s", &nomes[contadorNomes])  ;

printf("\nDigite o numero do assento requerido : ");
scanf("%d", &assentos[contadorAssentos]) ;




printf("\nNome do passageiro :  %s", nomes[contadorNomes]) ;


printf("\nAssento escolhido : %d",assentos[contadorAssentos]) ;



contadorAssentos ++ ;
contadorNomes ++ ;


printf("\n\nDeseja continuar ? <S/N>") ;
scanf(" %c", &escolha) ;




}

while ((escolha == 'S')|| (escolha == 's')) ;


}

What would be more recommended to go through the matrix and assign the value 1 exactly to the position given in the seat variable? How to get exactly in each position?

I think I’d use a for to go through, but I still can’t implement a way to relate the seat number to the position in the matrix.

Answer 1

The code is a little disorganized, does some unnecessary things like make loop to reset the matrix, has unnecessary variable, but it remains to close when it depletes the number of seats, report that the seat is already occupied and obviously occupy the seat, besides not showing a map (ok, the exercise does not ask, but it is the way to see if everything is right).

To know the row is easy, just divide by 6. You have to subtract 1 because the array starts at 0. Rounding the integer will ensure that the number is round. if dividing 9 by 6 will give 1 (would be 1.5, but a int has no decimal places).

I did as I was, but I think it would be better not to ask if you want to continue, if the seat was 0, I could finish.

The seat calculation is a little more complicated, but not much. Do the same count and then multiply by 6 again to get the position of the seat as if it had no rows. Take the seat number and subtract from the position found in the previous account, then you find the seat offset.

#include <stdio.h>

int main () {
    int assentos[300];
    char nomes[300][15];
    int ocupados[50][6] = { 0 };
    int contadorAssentos = 0;
    char escolha;
    do { 
        printf("\nDigite o nome do passageiro: ");
        scanf("%s", nomes[contadorAssentos]);
        printf("\nDigite o numero do assento requerido: ");
        scanf("%d", &assentos[contadorAssentos]);
        printf("\nNome do passageiro: %s", nomes[contadorAssentos]);
        printf("\nAssento escolhido: %d", assentos[contadorAssentos]);
        int fileira = (assentos[contadorAssentos] - 1) / 6;
        int assento = assentos[contadorAssentos] - 1 - fileira * 6;
        if (ocupados[fileira][assento]) printf("\nO assento já está ocupado, escolha outro!");
        ocupados[fileira][assento] = 1;
        if (contadorAssentos++ == 300) break;
        printf("\nDeseja continuar? <S/N>");
        scanf(" %c", &escolha);
    } while (escolha == 'S' || escolha == 's');
    printf("\n");
    for (int i = 0; i < 50; i++) {
        for (int j = 0; j < 6; j++) printf("F%02dA%d=%s | ", i + 1, j + 1, ocupados[i][j] ? "ocupado" : "livre  ");
        printf("\n");
    }
}

Behold working in the ideone. And in the repl it.. Also put on the Github for future reference.