looping error ,program stop and show "INPUT NOT VALID!!" but ask again for input?

Question

I have these two problems:

I have this code which will take number of hours. If total_hours is greater than 60, then it should stop. It does stop, but then it shows the messageINPUT NOT VALID!! and asks for input again (which it should not.)
Otherwise, is true the first input called "name" is not asked in the second time "when use put "Y" as an answer ".

Code:

#include <stdio.h>
#include <string.h>
int main() {
    int total_hours;
    char name[100], category[3], nic[140];
    float gross_pay, overtime_pay, net_pay;
    int straight_time = 44, pay_hour;
    char con;

    do {
        fgets(name, 100, stdin);

        printf("NIC:");
        fgets(nic, 140, stdin);

        printf("Category:");
        fgets(category, 3, stdin);

        printf("Total Hours:");
        scanf("%d", & total_hours);

        printf("\n\t\t  Smart Store Hypermarket \n");
        printf("============================================================\n");
        printf("Name:%s\nNIC:%s\nCategory:%s\nTotal Hours:%d\n\n", name, nic, category, total_hours);

        if (strncmp(category, "A1", 2) == 0) {
            pay_hour = 5;
        } else if (strncmp(category, "A2", 2) == 0) {
            pay_hour = 7;
        } else if (strncmp(category, "M1", 2) == 0) {
            pay_hour = 10;
        } else if (strncmp(category, "M2", 2) == 0) {
            pay_hour = 15;
        } else if (strncmp(category, "BB", 2) == 0) {
            pay_hour = 20;
        }

        if (total_hours > 44 && total_hours < 60) {
            gross_pay = straight_time * pay_hour;
            overtime_pay = pay_hour;
            net_pay = gross_pay + pay_hour;
            printf("Gross pay = %.2f RM\nOvertime pay =%.2f RM\nNet pay= %.2f RM\n", gross_pay, overtime_pay, net_pay);
            printf("\nContinue (Y/N) ? :");
            scanf("\n%c", &con);

        } else {
            printf("INPUT NOT VALID!!");
        }

    } while ((con != 'N'));
    getchar();
}

How do you want it to stop? Put a `return` in the `else` clause and it will `return` to the OS. — Fiddling Bits, Dec 16 '13 at 17:17
if user input a number in total_hours like 90 it should stop and show the message "INPUT NOT VALID!! "quit the program .not to ask user for more input — user3077137, Dec 16 '13 at 17:23
Put `return -1` or something like that right after `printf("INPUT NOT VALID!!");` and it will do that. — Fiddling Bits, Dec 16 '13 at 17:25
break did the trick ,how about why the second time "when use put "Y" as an answer ".can not input "name " but the others work fine — user3077137, Dec 16 '13 at 17:28
Do you mean, `return` did the trick? `break` would work too but it would return nothing to the OS, which is something bad (i.e. undefined behavior). — Fiddling Bits, Dec 16 '13 at 17:31

score 0 · Accepted Answer · edited May 23 '17 at 12:19

0

Put a break statement after the line printf("INPUT NOT VALID!!"); to exit the loop instead of repeating it.

As for your other issue, Running fgets after a scanf can cause it to receive an empty line. See this question for the reason and solutions.

edited May 23 '17 at 12:19

Community

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answered Dec 16 '13 at 17:20

interjay

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yes break did the trick ,how about why the second time "when use put "Y" as an answer ".can not input "name " but the others work fine . – user3077137 Dec 16 '13 at 17:27
That's what I explained in the second paragraph, it's due to mixing `fgets` and `scanf`. – interjay Dec 16 '13 at 17:28
what can we do about it ?! – user3077137 Dec 16 '13 at 17:34
Did you read the linked question? It contains several solutions, for example putting `while ((c = getchar()) != '\n' && c != EOF); ` after the `scanf`. – interjay Dec 16 '13 at 17:45

looping error ,program stop and show "INPUT NOT VALID!!" but ask again for input?

1 Answers1