Question

I need to write a program that takes input line at a time and output only the lines that have two tokens. Assume input is no longer than 50 bytes. I used fgets to capture one line at a time and used sscanf to grab token at a time and see if it returns 2. However, it doesn’t seem to work. Can someone suggest how to do it?

#include <stdio.h>

int main(void)
{
    char buff[50];
    char token[50];
    int number;

    while (fgets(buff, sizeof(buff), stdin) != NULL)
    {
        while ((number = sscanf(buff, "%s", token)) != EOF)
        {
            number = sscanf(buff, "%s", token);
            if (number == 2)
            {
                printf("%s\t", token);
            }
        }
    }
    return 0;
}

Answer 1

This works..

#include <stdio.h>

int main(void)
{
    char buff[50];
    char token1[50];
    char token2[50];
    char token3[50];

    while (fgets(buff, sizeof(buff), stdin) != NULL)
    {

        if (sscanf(buff, "%s%s%s", token1, token2, token3) == 2)
        {
            printf("%s %s\n", token1, token2);
        }
    }
    return 0;
}