#include <stdio.h>

int
main(void)
{
    int v = 0;
    int c;

    printf("input number=");

    while ((c = getchar()) != EOF) {
	if (c >= '0' && c <= '9')
	    v = v*10 + (c - '0');
	else
	    break;
    }

/*
    while ((c = getchar()) != EOF) {
	if (isdigit(c))
	    v = v*10 + (c - '0');
	else
	    break;
    }
*/

    printf("v=%d\n", v);
}