Help with for loop and nested if's

[Gil Carvalho]

Hi

I have a problem with this code, acting strange

I need a for loop to ask 2 questions, if the user gives a wrong answer, the user still another chance to get 1 point, the code is working but if the first answer is wrong and the second is right, the program still give me more questions....

anyone knows whats wrong here??

void gp1_Ques(struct perg *p, char *usr1)
{
    FILE *f; //apontador para ficheiro
    f=fopen("gp1.dat", "r"); //abertura do ficheiro
    int reg=0,reg1, i; //Variaveis contadoras de perguntas e random
    int random; // Variável de random
    int op, resposta; //Variáveis opções utilizadores
    int qual, result=0; //Variáveis resultados
    rewind(f); //retorna a posição corrente do ficheiro para o início
    srand(time(NULL)); //função random
    system("cls");
    fseek(f, 0, SEEK_END);
    reg=ftell(f) /sizeof *p;
    fseek(f, 0 , SEEK_SET);
    if (reg<=0) //condição que verifica se existem registos
    {
        printf ("Sem registos \n");
        printf ("\n Necessario ter registos para jogar...\n");
        return;
        }
        else
        {
            printf ("\n*=============================================================================*\n");
            printf ("|                       >>>>Visualizao de perguntas<<<<                        |\n");
            printf ("*=============================================================================*\n");
            printf ("                                                                               \n");
            printf ("\n      TOTAL de perguntas: %d \n",reg); //conta as perguntas
            printf ("\n      O seu score maximo sera: %d\n",reg/10); //pontuação máxima do jogo
            qual = reg-19; //contagem minima para passar de fase
            printf ("\n      Para a qualificacao precisa de: %d\n",qual); //total minimo para passar fase
            //testes para ver se funciona o random
            random=rand()%reg; //função random
            reg1 = random; //atribui a variavel reg o valor de random
            }
            printf("\n\n\n      Quer comecar a jogar ?(Sim=1; Nao=0) \n");
            printf ("*=============================================================================*\n");
            scanf("%d", &op);
            system("cls");
            if(op==1)
            {
                for(i=0; i<=2;i++)
                {
                    fseek(f, reg1 * sizeof *p, SEEK_SET);
                    fread(p, sizeof *p, 1, f);
                    printf("Bemvindo ao jogo %s", usr1);
                    printf("\nPergunta : %s", p->ques);
                    printf("\nOpcao 1 : %s",p->op1);
                    printf("\nOpcao 2 : %s",p->op2);
                    printf("\nOpcao 3 : %s",p->op3);
                    printf("\nOpcao 4 : %s",p->op4);
                    printf("\nResposta correta?\n");
                    scanf("%d", &resposta);
                    getchar();
                    if(resposta==p->res)
                    {
                        printf("\nRight answer...\n");
                        result++;
                        random=rand()%reg; //random
                        reg1 = random; //
                        fseek(f, reg1 * sizeof *p, SEEK_SET);
                        fread(p, sizeof *p, 1, f);
                        printf("\nPergunta : %s", p->ques);
                        printf("\nOpcao 1 : %s",p->op1);
                        printf("\nOpcao 2 : %s",p->op2);
                        printf("\nOpcao 3 : %s",p->op3);
                        printf("\nOpcao 4 : %s",p->op4);
                        printf("\nRight answer?\n");
                        scanf("%d", &resposta);
                        getchar();
                        if(resposta==p->res)
                        {
                            printf("\nRight answer\n");
                            result++;
                        }
                        else
                        {
                            printf("Wrong...\n");
                        }
                    }
                    else
                    {
                        printf("One mor chance \n");
                        random=rand()%reg; //random
                        reg1 = random; //
                        fseek(f, reg1 * sizeof *p, SEEK_SET);
                        fread(p, sizeof *p, 1, f);
                        printf("\nPergunta : %s", p->ques);
                        printf("\nOpcao 1 : %s",p->op1);
                        printf("\nOpcao 2 : %s",p->op2);
                        printf("\nOpcao 3 : %s",p->op3);
                        printf("\nOpcao 4 : %s",p->op4);
                        printf("\nRight answer?\n");
                        scanf("%d", &resposta);
                        getchar();
                        if(resposta==p->res)
                        {
                            printf("\nRight answer...\n");
                            result++;
                        }
                        else
                        {
                            printf("Wrong...\n");


                        }
                    }
                }
            }
            else if (op==0)
            {
                jogo();
            }
            else
            {
                printf("\n Invalid option\n");
                Sleep(2000);
                jogo();
            }
        fclose(f);
}

[Malcolm McLean]

You've got a for loop and an if.

You need to either get rid of the for loop, or use break if the user types in the right answer.

[Gil Carvalho]

Good morning

Thank's for your help
Iv'e already changed an get rid of the loop but i still have some problems
This is how a build my if statement (just the if, not all function)

 if(op==1) //The user choose the option 1 and will have 2 question to answer
            {
                fseek(f, reg1 * sizeof *p, SEEK_SET);
                fread(p, sizeof *p, 1, f);
                printf("Bemvindo ao jogo %s", usr1);
                printf("\nPergunta : %s", p->ques);
                printf("\nOpcao 1 : %s",p->op1);
                printf("\nOpcao 2 : %s",p->op2);
                printf("\nOpcao 3 : %s",p->op3);
                printf("\nOpcao 4 : %s",p->op4);
                printf("\nResposta correta?\n");
                scanf("%d", &resposta);
                getchar();
                if(resposta==p->res)
                {
                    printf("\nAcertou na resposta...\n");
                    result++;
                    random=rand()%reg; //função random
                    reg1 = random; //atribui a variavel reg o valor de random
                    fseek(f, reg1 * sizeof *p, SEEK_SET);
                    fread(p, sizeof *p, 1, f);
                    printf("\nPergunta : %s", p->ques);
                    printf("\nOpcao 1 : %s",p->op1);
                    printf("\nOpcao 2 : %s",p->op2);
                    printf("\nOpcao 3 : %s",p->op3);
                    printf("\nOpcao 4 : %s",p->op4);
                    printf("\nResposta correta?\n");
                    scanf("%d", &resposta);
                    getchar();
                    if(resposta==p->res)
                    {
                        printf("\nAcertou novamente na resposta...\n");
                        result++;
                    }
                    else
                    {
                        printf("Errou nesta questao...\n");
                    }
                }
                else //if the user fails the fisrt question
                {
                    printf("Tem mais uma tentativa para atingir o minimo \n");
                    random=rand()%reg; //função random
                    reg1 = random; //atribui a variavel reg o valor de random
                    fseek(f, reg1 * sizeof *p, SEEK_SET);
                    fread(p, sizeof *p, 1, f);
                    printf("\nPergunta : %s", p->ques);
                    printf("\nOpcao 1 : %s",p->op1);
                    printf("\nOpcao 2 : %s",p->op2);
                    printf("\nOpcao 3 : %s",p->op3);
                    printf("\nOpcao 4 : %s",p->op4);
                    printf("\nResposta correta?\n");
                    scanf("%d", &resposta);
                    getchar();
                    if(resposta==p->res)
                    {
                        printf("\nAcertou na resposta...\n");
                        result++;
                    }
                    else
                    {
                        printf("Errou novamente...ai esta cultura geral!!! \n");
                    }
                }
                if (result>=1) //Last if statement to count the result (0, if the two answer are wrong) (1 if one is right) (2 if both are right)
                {
                    printf("Teve pontuacao de %d\n", result);
                    printf("Vai passar para a fase 2...aguarde \n");
                    //Sleep(2000);
                    gp2_Ques(&p, usr1, result); //call the next function
                }
                else
                {
                    printf("Nao atingiu o minimo para seguir....vai voltar ao menu anterior");
                    Sleep(2000);
                    jogo();
                }
            }
            else if(op==0)
            {
                jogo();
            }
            else
            {
                printf("\n     Opcao invalida...vai regressar ao menu anterior\n");
                Sleep(2000);
                jogo();
            }
}

What do you think??

[Salem]

It might be clearer if you created another function, instead of copy/pasting.

Eg.

int askAQuestion ( FILE *f, int res1 ) {
  struct perg p;
  fseek(f, reg1 * sizeof p, SEEK_SET);
  fread(p, sizeof p, 1, f);
  printf("Bemvindo ao jogo %s", usr1);
  printf("\nPergunta : %s", p.ques);
  printf("\nOpcao 1 : %s",p.op1);
  printf("\nOpcao 2 : %s",p.op2);
  printf("\nOpcao 3 : %s",p.op3);
  printf("\nOpcao 4 : %s",p.op4);
  printf("\nResposta correta?\n");
  scanf("%d", &resposta);
  getchar();
  if(resposta==p.res)
    return 1;
  else
    return 0;
}

Then your code might be clearer as

  if ( askAQuestion(f,reg1) ) {
    printf("\nAcertou na resposta...\n");
    result++;
    random=rand()%reg; //função random
    if ( askAQuestion(f,random) ) {
      printf("\nAcertou novamente na resposta...\n");
      result++;
    } else {
      printf("Errou nesta questao...\n");
    }
  }

[Gil Carvalho]

Hi Salem

Interesting approach, didn't think about that like this.
Let me try implement this way.

Thanks

[Salem]

There's a basic rule of thumb

void someFunction ( ) { //!! this
  // some code
} //!! this

that states if you can't see the open and closing brace of a function on screen at the same time, then the function is too long.

[Gil Carvalho]

Can you explain me this please

if(result1==3)
            {
                printf("\nYou have  %d points", result1);
                printf("You have %d from last stage", result);
                result+=result1;
                printf("\nThe total earned is  %d\n", result);
            }

result = 2
result1 = 3
The print is 14????

It should be 5, right?

[Salem]

I'm sure if you try it in an isolated program, like

int main ( ) {
    int result = 2, result1 = 3;
    printf("\nYou have  %d points", result1);
    printf("You have %d from last stage", result);
    result+=result1;
    printf("\nThe total earned is  %d\n", result);
    return 0;
}

you'll get 5 printed.

Which means in your large program, something has almost certainly trashed memory and your erroneous printf() is just where it shows up.

[Gil Carvalho]

Hi Salem

Can it be because of this warning in this line ?

warning: format '%d' expects argument of type 'int', but argument 3 has type 'int *' [-Wformat]|

void gp2_Ques(struct gp2 *p, char *usr1, int *result)

printf("%s transporta %d pontos da anterior fase \n",usr1, result);

I'm prety sure it must be, that result comes from another function but the strange is that i have the correct value...

[Salem]

Wait, result is a pointer!?

Yes, you need to fix the printf.

You also need to fix the code as well.

printf("\nYou have  %d points", result1);
printf("You have %d from last stage", *result);
*result+=result1;
printf("\nThe total earned is  %d\n", *result);

[Gil Carvalho]

Hi

With *result the program gives segmentation fault.

So my problem is, how to get the value of result from the main funtion

void gp1_Ques(struct perg *p, char *usr1)
{
    FILE *f; //apontador para ficheiro
    f=fopen("gp1.dat", "r"); //abertura do ficheiro
    int reg=0,reg1; //Variaveis contadoras de perguntas e random
    int random; // Variável de random
    int result=0; //Variáveis resultados
}

Then is the new function

void gp2_Ques(struct gp2 *p, char *usr1, int *res)
{
    FILE *f; //apontador para ficheiro
    f=fopen("gp2.dat", "rb"); //abertura do ficheiro
    int reg=0,reg1; //Variaveis contadoras de perguntas e random
    int random; // Variável de random
    int result1=0; //Variáveis resultados
}

Should the prototype be like this?
then
gp1_Ques(*result)


Thanks