c_ch01_ex09.c

/*Exercise 1-9. Write a program to copy its input to its output, replacing each string of one or more blanks by a single blank*/

#include <stdio.h>
int main()
{
        int flag = 0, c;
        while ((c = getchar()) != EOF) {
                if (c == ' ') {
                        if (flag == 0) {
                                putchar(c);
                                flag = 1;
                        }
                } else {
                        putchar(c);
                        flag = 0;
                }
        }
        return 0;
}