程序代码：

int countmins(int n, int u, int d)
{
    if (n < 0 || n > 100 || d > u || d < 0 || u < 0) {
        printf("input error!\n")
        return -1;
    }
    int i;
    int step = u - d;
    for (i = 1; n - 1 - i * step > step; ++i)
        ;
    return i * 2  + 1;
}

程序代码：

#include
int main()
{
  int n, u, d;
  while(scanf("%d%d%d", &n, &u, &d), n)
    printf("%d\n", (n - d - 1) / (u - d) * 2 + 1);
  return 0;
}

程序代码：

#include<stdio.h>
int main()
{
  int n, u, d;
  while(scanf("%d%d%d", &n, &u, &d), n)
    if(n <= u) printf("1\n"); else printf("%d\n", (n - d - 1) / (u - d) * 2 + 1);
  return 0;
}

程序代码：

/*
An inch worm is at the bottom of a well n inches deep. It has enough energy to climb u inches every minute, but then has to rest a minute
before climbing again. During the rest, it slips down d inches. The process of climbing and resting then repeats. How long before the worm
climbs out of the well? We'll always count a portion of a minute as a whole minute and if the worm just reaches the top of the well at the
end of its climbing, we'll assume the worm makes it out.

Input

 There will be multiple problem instances. Each line will contain 3 positive integers n, u and d. These give the values mentioned in the

 paragraph above. Furthermore, you may assume d < u and n < 100. A value of n = 0 indicates end of output.

Output

 Each input instance should generate a single integer on a line, indicating the number of minutes it takes for the worm to climb out of the

 well.

Sample Input

 10 2 1

 20 3 1

 0 0 0

Sample Output

 17

 19
*/

#include <stdio.h>
#include <conio.h>
#include <string.h>

int IsDigit(char Character);
void EatSpaces(char* String);
int Str2Int(char* String);

void main(void)
{
    char Buffer[1024];
    int Deep;                    // 洞的深度
    int Up;                        // 每分钟爬升的高度
    int Down;                    // 每分钟下落的高度
    double Speed;                // 速率(英寸/秒)
    int Total_Time;                // 总时间(秒)
    int Time;                    // 分段时间(秒)
    double y;                    // y轴坐标
    int Uping;                    // 处于爬升阶段

    printf_s("蠕虫爬升问题\n\n");

    for (; ;)
    {
        // 接收数据
        do
        {
            printf_s("洞的深度(英寸) [输入0结束程序] n = ");
            Buffer[0] = '\0';
            gets_s(Buffer, 79);
            EatSpaces(Buffer);
            Deep = Str2Int(Buffer);
        } while (Deep < 0);
        if (Deep == 0)
        {
            break;
        }
        do
        {
            printf_s("每分钟爬升的高度(英寸) u = ");
            Buffer[0] = '\0';
            gets_s(Buffer, 79);
            EatSpaces(Buffer);
            Up = Str2Int(Buffer);
        } while (Up <= 1);
        do
        {
            printf_s("每分钟下落的高度(英寸) d = ");
            Buffer[0] = '\0';
            gets_s(Buffer, 79);
            EatSpaces(Buffer);
            Down = Str2Int(Buffer);
        } while ((Down <= 0) || (Down >= Up));

        // 模拟爬升运动
        Total_Time = 0;
        Time = 0;
        y = -Deep + 1;            // 考虑蠕虫本身长度1英寸
        Uping = 1;
        while (y < 0)
        {
            if (Uping)
            {
                if (Time < 59)
                {
                    Speed = Up / 60.0;
                }
                else
                {
                    Uping = 0;
                    Time = 0;
                }
            }
            if (!Uping)
            {
                if (Time < 59)
                {
                    Speed = -Down / 60.0;
                }
                else
                {
                    Uping = 1;
                    Time = 0;
                }
            }
            y += Speed;
            Time++;
            Total_Time++;
        }
        printf_s("爬行总时间为%.2f分钟\n\n", Total_Time / 60.0);
    }
}

// 判断一字符是否数字字符
int IsDigit(char Character)
{
    if ((Character >= '0') && (Character <= '9'))
    {
        return 1;
    }
    else
    {
        return 0;
    }
}

// 删除字符串的空格
void EatSpaces(char* String)
{
    int i = 0;
    int j = 0;

    while (( *(String + i) = *(String + j++)) != '\0')
    {
        if (*(String + i) != ' ')
        {
            i++;
        }
    }
    return;
}

// 字符串转为整数
int Str2Int(char* String)
{
    int IsNegative = 0;
    int nVar = 0;

    if (*String == '-')
    {
        IsNegative = 1;
        String++;
    }
    while (*String && IsDigit(*String))
    {
        nVar = nVar * 10 + *String - '0';
        String++;
    }
    if (IsNegative)
    {
        nVar = -nVar;
    }
    return nVar;
}