7-17 crawling worms (break exercise)

A worm is long 1 " , In a deep for N The bottom of the well . Known worms every 1 Minutes to climb up U " , But must rest 1 Minutes to climb up . In the process of rest , The worm has slipped again D " . That's it , Go up and down again . Excuse me, , How long does it take for the worm to climb out of the well ？

There is not enough demand here 1 Minutes press 1 Minute meter , And assume that as long as the head of the worm reaches the top of the well during a climb , So the worm is done . At the beginning , Worms lie at the bottom of the well （ That is, the height is 0）.

Input format ：

The input is given in order on one line 3 A positive integer N、U、D, among D<U,N No more than 100.

Output format ：

Output the time when the worm climbed out of the well in one line , In minutes .

Examples ："> sample input ：

12 3 1

sample output ：

11

Code ： 

#include<stdio.h>
int main()
{
    int N,U,D,time=0,high=0;
    scanf("%d%d%d",&N,&U,&D);
    while(high<N)
    {
        high+=U;
        time++;
        if(high>=N)
   	    break; // If the height has been reached or exceeded , No more rest . So jump out of the loop 
        high-=D;
        time++;
    }
    printf("%d",time);
}