分析这段代码 if((Set_floor & (1<<(Current_floor - 1))) == (1<<(Current_floor - 1)))
时间: 2023-05-15 07:04:35 浏览: 59
可以使用哈希表来解决这个问题,首先遍历一遍列表,将每个数出现的次数记录在哈希表中,然后再遍历一遍列表,找到只出现一次的数即可。以下是示例代码:
```
def find_unique(nums):
count = {}
for num in nums:
if num in count:
count[num] += 1
else:
count[num] = 1
for num in nums:
if count[num] == 1:
return num
return None
```
这个函数接受一个列表作为参数,返回列表中只出现一次的数。如果没有这样的数,则返回 None。
相关问题
写一段可以控制三层电梯的verilog语言代码
以下是一个简单的控制三层电梯的Verilog语言代码,包括电梯的状态机和控制逻辑:
```
module elevator (
input clk,
input rst,
input up_button,
input down_button,
input [2:0] floor_sensor,
output reg [2:0] floor
);
// Define the states
parameter IDLE = 2'b00;
parameter MOVING_UP = 2'b01;
parameter MOVING_DOWN = 2'b10;
// Define the floor constants
parameter FLOOR_1 = 3'b000;
parameter FLOOR_2 = 3'b001;
parameter FLOOR_3 = 3'b010;
// Define the state and floor variables
reg [1:0] state;
reg [2:0] current_floor;
// Set the initial state and floor
initial begin
state = IDLE;
current_floor = FLOOR_1;
end
// Define the state machine
always @ (posedge clk or posedge rst) begin
if (rst) begin
state <= IDLE;
current_floor <= FLOOR_1;
end else begin
case (state)
IDLE: begin
if (up_button && current_floor != FLOOR_3) begin
state <= MOVING_UP;
end else if (down_button && current_floor != FLOOR_1) begin
state <= MOVING_DOWN;
end
end
MOVING_UP: begin
if (floor_sensor[current_floor+1]) begin
current_floor <= current_floor + 1;
state <= IDLE;
end
end
MOVING_DOWN: begin
if (floor_sensor[current_floor-1]) begin
current_floor <= current_floor - 1;
state <= IDLE;
end
end
endcase
end
end
// Set the floor output
always @ (current_floor) begin
case (current_floor)
FLOOR_1: floor = FLOOR_1;
FLOOR_2: floor = FLOOR_2;
FLOOR_3: floor = FLOOR_3;
endcase
end
endmodule
```
该代码使用状态机模型控制电梯的状态,并根据输入的按钮和传感器信号来决定电梯的运动方向和停靠楼层。在每个时钟周期中,状态机会检查当前状态并执行相应的操作,例如启动电梯或将其停靠在所需的楼层。输出端口 floor 显示当前电梯所在的楼层。
将这段代码中的ts语法去掉import { useEffect, useState } from 'react'; import moment from 'moment'; export interface ICountdown { deadline: string; format?: 'YYYY-MM-DD HH:mm:ss' | string; } export type Remains = Record<'day' | 'hour' | 'minute' | 'second', number>; const useCountdown = ({ deadline, format = 'YYYY-MM-DD HH:mm:ss', }: ICountdown): Remains => { const [{ current, updater }, setCurrent] = useState({ current: moment(), updater: 0, }); const [remains, setRemains] = useState<Remains>({ day: 0, hour: 0, minute: 0, second: 0, }); useEffect(() => { const timer = window.setInterval(() => { current.isSameOrAfter(moment(deadline, format)) ? clearInterval(timer) : setCurrent(prev => ({ current: prev.current.add(1, 's'), updater: prev.updater + 1, })); }, 1000); return () => clearInterval(timer); }, [deadline]); useEffect(() => { let millisec = moment(deadline, format).valueOf() - current.valueOf(); millisec = millisec >= 0 ? millisec : 0; setRemains({ day: Math.floor(millisec / (1000 * 60 * 60 * 24)), hour: Math.floor((millisec / (1000 * 60 * 60)) % 24), minute: Math.floor((millisec / (1000 * 60)) % 60), second: Math.round((millisec / 1000) % 60), }); }, [updater]); return remains; }; export default useCountdown;
去掉ts语法后的代码如下:
import React, { useEffect, useState } from 'react';
import moment from 'moment';
const useCountdown = ({
deadline,
format = 'YYYY-MM-DD HH:mm:ss',
}) => {
const [current, setCurrent] = useState(moment());
const [updater, setUpdater] = useState(0);
const [remains, setRemains] = useState({
day: 0,
hour: 0,
minute: 0,
second: 0,
});
useEffect(() => {
const timer = window.setInterval(() => {
const newCurrent = current.add(1, 's');
if (newCurrent.isSameOrAfter(moment(deadline, format))) {
clearInterval(timer);
} else {
setCurrent(newCurrent);
setUpdater(prev => prev + 1);
}
}, 1000);
return () => clearInterval(timer);
}, [deadline]);
useEffect(() => {
let millisec = moment(deadline, format).valueOf() - current.valueOf();
millisec = millisec >= 0 ? millisec : 0;
setRemains({
day: Math.floor(millisec / (1000 * 60 * 60 * 24)),
hour: Math.floor((millisec / (1000 * 60 * 60)) % 24),
minute: Math.floor((millisec / (1000 * 60)) % 60),
second: Math.round((millisec / 1000) % 60),
});
}, [updater]);
return remains;
};
export default useCountdown;