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QOJ

Time Limit: 1 s Memory Limit: 1024 MB Total points: 100
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假设 Bobo 位于时间轴(数轴)上 $t_0$ 点,他要使用时间机器回到区间 $(0, h]$ 中。

当 Bobo 位于时间轴上 $t$ 点,同时时间机器有 $c$ 单位燃料时,他可以选择一个满足 $\lceil \frac{x}{h}\rceil \cdot h \leq c$ 的非负整数 $x$, 那么时间机器会在 $[0, x]$ 中随机整数 $y$,使 Bobo 回到 $(t - y)$ 点,同时消耗 $y$ 单位燃料。 (其中 $\lceil \cdot \rceil$ 表示上取整)

因为时间机器的随机性,对于给出的参数 $h$ 和时间机器剩余燃料 $c$,Bobo 想知道能够保证回到区间 $(0, h]$ 中的 $t_0$ 的最大值。

输入格式

输入文件包含多组数据,请处理到文件结束。

每组数据包含 $2$ 个整数 $h$ 和 $c$.

输出格式

对于每组数据输出 $1$ 个整数表示 $t_0$ 的最大值。

样例输入

100 99
100 100
100 149

样例输出

100
101
150

样例解释

对于第一组样例,因为剩余燃料 $c = 99 < 100$,Bobo 只能选择 $x = 0$,从而 $y = 0$。所以当 $t_0 > h = 100$ 时,Bobo 一定无法回到目标区间。

对于第二组样例,当 $t_0 = 102$ 时,选择 $x = 2$,可能随机到 $y = 1$,此时位于 $t = 99$,燃料 $c = 99$,任务失败。所以 $t_0 < 102$.

数据范围

  • $1 \leq h \leq 10^9$
  • $0 \leq c \leq 10^9$
  • 数据组数不超过 $10^5$.

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