Error when printing static list

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Error when printing static list

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#1 by (2 votes)

6

How do I print to my static list?

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

#define MAX 3

struct alunos {
    int matricula;
    char nome[30];
    float nota1, nota2;
};

typedef struct lista {
    int quant;
    struct alunos dados[MAX];

} Lista;

Lista* cria_Lista() {

    Lista* l;
    l = (Lista*) malloc(sizeof(struct lista));

    if(l != NULL)
        l->quant = 0;

    return l;
}

void libera_Lista(Lista* l) {
    free(l);
}




int insere_final(Lista* l, struct alunos al) {

    if(l == NULL || lista_Cheia(l))
        return 0;

    l->dados[l->quant] = al;
    l->quant++;

    return 1;
}

int insere_inicio(Lista *l, struct alunos al) {

    if(l == NULL || lista_Cheia(l))
        return 0;

    int i;
    for(i= l->quant - 1; i>=0; i--) {
        l->dados[i + 1] = l->dados[i]; //proxima posicao e igual a atual
        l->dados[0] = al; //pega a primeira posicao
        l->quant++; //incrementa quantidade
        return 1;
    }

}

void imprime_lista(Lista* l) {

    if(l == NULL)
        return; // nao retorna nada

    int i; //variavel auxiliar
    for(i=0; i < l->quant; i++)
        printf("Matricula: %d\n", l->dados[i].matricula);
        printf("Nome: %s\n", l->dados[i].nome);
        printf("Notas: %f %f\n", l->dados[i].nota1, l->dados[i].nota2);


}



int main()
{
 struct alunos al[2] = {{3, "João", 8.45, 9.98},
  {1, "Maria", 6.75, 8.54}};

 Lista *l;
 l  = cria_Lista();

 int i;

 for(i=0; i<2; i++) {
        insere_inicio(l, al[0]);
 imprime_lista(l);

 }
libera_Lista(l);
    return 0;
}

You are printing empty values, I believe that the statement should be wrong after main .

c lista

asked by anonymous 10.10.2016 / 18:05

1 answer

Argument of a function is another function Copy a numpy.array without modifying the original

score 2 · Accepted Answer

The code had so many errors that I can not remember all the ones I fixed. I will try to describe them comparing what is in the question and what was in mine that still has several problems, I did not try to solve everything, just to make it work.

I took the comments that were of no use and gave an organized and modernized.

The main error in printing is the lack of keys in for . The ideal is to always put a key, even if you do not need it, so avoid mistakes by carelessness.

The insert function at the beginning did not insert anything, it only made the data shift, which even ended at the first interaction. I do not think this is ideal and I do not know if it is doing it right.

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

#define MAX 3

typedef struct alunos {
    int matricula;
    char nome[30];
    float nota1, nota2;
} Alunos;

typedef struct lista {
    int quant;
    Alunos dados[MAX];

} Lista;

Lista* cria_Lista() {
    Lista* l = malloc(sizeof(Lista));
    if (l != NULL) {
        l->quant = 0;
    }
    return l;
}

void libera_Lista(Lista* l) {
    free(l);
}

int insere_final(Lista* l, Alunos al) {
    if (l == NULL) { // || lista_Cheia(l)) { --- tirei porque a função não existe
        return 0;
    }
    l->dados[l->quant] = al;
    l->quant++;
    return 1;
}

int insere_inicio(Lista *l, Alunos al) {
    if (l == NULL) { // || lista_Cheia(l)) { --- tirei porque a função não existe
        return 0;
    }
    for (int i = l->quant - 1; i >= 0; i--) {
        l->dados[i + 1] = l->dados[i];
        l->dados[0] = al;
        l->quant++;
    }
    l->dados[0] = al;
    l->quant++;
    return 1;
}

void imprime_lista(Lista* l) {
    if (l == NULL) {
        return;
    }
    for(int i = 0; i < l->quant; i++) {
        printf("Matricula: %d\n", l->dados[i].matricula);
        printf("Nome: %s\n", l->dados[i].nome);
        printf("Notas: %f %f\n", l->dados[i].nota1, l->dados[i].nota2);
    }
}

int main() {
    Alunos al[2] = {{3, "João", 8.45, 9.98}, {1, "Maria", 6.75, 8.54}};
    Lista *l = cria_Lista();
    for (int i = 0; i < 2; i++) {
        insere_inicio(l, al[i]);
        imprime_lista(l);
    }
    libera_Lista(l);
}

See running on ideone and on CodingGround .