CODEWITHSUNDEEP
cfunctionscanf
Thedonor
Thedonor

Reputation: 5

How can i control the behaviour of scanf when it needs an int value but is passed a character?

I'm doing a small progect(tic tac toe) and i have a function that controls game modes based on the input of the player. Now let's suppose the player inserts a character instead of the three legal values (0,1,2). Now if the player passes a character the default value isn't changed so the while loop becomes infinite. So i have tried to create a value readedCharac that stores the number of characters readed from scanf but it doesn't resolve the problem. What am I missing? Thanks for your awnsers

    int playerChoice = -1;
    int readedCharac = 0;

    printf("\n\nWELCOME TO TIC-TAC-TOE GAME\n\n");
    mainMenu();
    readedCharac = scanf("%d",&playerChoice);

    while((playerChoice < 0 || playerChoice > 2) && readedCharac == 0 )
    {
        printf("\nInvelid Entry Retry \n");
        scanf("%d",&playerChoice);
    }

Upvotes: 0

Views: 37

Answers (1)

SM2A
SM2A

Reputation: 535

This happens because buffer of scanf still looking for integer and so its not available . You can empty the buffer by :

fflush(stdin);

This might not work in all operating systems , next thing you can do is use code below to empty the buffer :

while(getchar()!='\n');

So:

int playerChoice = -1;
int readedCharac = 0;

printf("\n\nWELCOME TO TIC-TAC-TOE GAME\n\n");
mainMenu();
readedCharac = scanf("%d",&playerChoice);

while((playerChoice < 0 || playerChoice > 2) && readedCharac == 0 )
{
    while(getchar()!='\n');
    printf("\nInvelid Entry Retry \n");
    scanf("%d",&playerChoice); 
}

Upvotes: 1

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