每个单词一行

有两个程序，第一个有用，第二个没用。我也不知道是为什么，希望知道的人告诉我一下。
还有个问题：如果单词之间有2个空格之类的话，程序输出时会在单词之间多出一个空行。

#include <stdio.h>
int main()
{
        int has_a_return = 0;
        int c;
        while((c = getchar()) != EOF){
                if(c == '\n' || c == ' ' || c == '\t')
                        has_a_return = 1;
                else
                        putchar(c);
                if(has_a_return == 1){
                        printf("\n");
                        has_a_return = 0;
                }
        }
        return 0;
}


#include <stdio.h>
int main()
{
        int has_a_return = 0;
        int c;
        while((c = getchar()) != EOF){
                if(c != '\n' || c != ' ' || c != '\t')
                        putchar(c);
                else
                        has_a_return = 1;
                if(has_a_return == 1){
                        printf("\n");
                        has_a_return = 0;
                }
        }
        return 0;
}