HDU 1302 The Snail

题目地址：​​点击打开链接​​

AC代码：

#include<stdio.h>
int main()
{
  double h,u,d,f,sum,down;
  int day,flag;
  while(scanf("%lf%lf%lf%lf",&h,&u,&d,&f) && h)
  {
    flag = 1;
    day = 0;
    sum = 0;
    f = f / 100;
    down = f * u;
    while(sum < h)
    {
      day++;
      sum += u;
      if(sum > h)
        break;
      sum -= d;
      if(sum < 0)
      {
        flag = 0;
        break;
      }
      u -= down; 
      if(u < 0)
      {
        day++;
        flag = 0;
        break;
      }
    }
    if(flag)
      printf("success on day %d\n",day);
    else
      printf("failure on day %d\n",day);
  }
  return 0;
}