#include <stdio.h> 
  
int main() 
{ 
    int n; 
    FILE *pf = fopen("1.txt", "w+"); 
    if (!pf) 
    { 
        puts("open file error!"); 
        return -1; 
    } 
    while (true) 
    { 
        printf("input a num:"); 
        scanf("%d", &n); 
        if (n==-1) 
            break; 
        fprintf(pf, "%d ", n); 
    } 
    fclose(pf); 
    puts("ok!"); 
    return 0; 
}