1184. Distance between bus stops: simple simulation problem

Title Description

This is a LeetCode Upper 1184. The distance between bus stops , The difficulty is Simple .

Tag : 「 simulation 」

There are... On the circular bus route    Individual station , From    To    Number . We know the distance between each pair of adjacent bus stops ,  Indicates that the number is    The station and number are  (i + 1) % n  The distance between the stations .

The buses on the loop line can travel clockwise and counterclockwise .

Return passengers from the starting point  start  Destination  destination  The shortest distance between .

Example 1：

 Input ：distance = [1,2,3,4], start = 0, destination = 1

 Output ：1

 explain ： Bus stop  0  and  1  The distance between them is  1  or  9, The minimum is  1.

Example 2：

 Input ：distance = [1,2,3,4], start = 0, destination = 2

 Output ：3

 explain ： Bus stop  0  and  2  The distance between them is  3  or  7, The minimum is  3.

Example 3：

 Input ：distance = [1,2,3,4], start = 0, destination = 3

 Output ：4

 explain ： Bus stop  0  and  3  The distance between them is  6  or  4, The minimum is  4.

Tips ：

simulation

Simulate according to the meaning of the question .

use i and j The pointer representing forward and backward respectively ,a and b Calculate the total cost of the two methods respectively .

Java Code ：

class Solution {
    public int distanceBetweenBusStops(int[] dist, int s, int t) {
        int n = dist.length, i = s, j = s, a = 0, b = 0;
        while (i != t) {
            a += dist[i];
            if (++i == n) i = 0;
        }
        while (j != t) {
            if (--j < 0) j = n - 1; 
            b += dist[j];
        }
        return Math.min(a, b);
    }
}

TypeScript Code ：

function distanceBetweenBusStops(dist: number[], s: number, t: number): number {
    let n = dist.length, i = s, j = s, a = 0, b = 0
    while (i != t) {
        a += dist[i]
        if (++i == n) i = 0
    }
    while (j != t) {
        if (--j < 0) j = n - 1
        b += dist[j]
    }
    return Math.min(a, b)
};

• Time complexity ：
• Spatial complexity ：

Last

This is us. 「 Brush through LeetCode」 The first of the series No.1184 piece , The series begins with 2021/01/01, As of the start date LeetCode I have in common 1916 questions , Part of it is a locked question , We will finish all the questions without lock first .

In this series , In addition to explaining the idea of solving problems , And give the most concise code possible . If the general solution is involved, there will be corresponding code templates .

In order to facilitate the students to debug and submit code on the computer , I've built a warehouse ：https://github.com/SharingSource/LogicStack-LeetCode .

In the warehouse address , You can see the links to the series 、 The corresponding code of the series 、LeetCode Links to the original problem and other preferred solutions .

More, more, more popular 「 written examination / interview 」 Relevant information can be found in the beautifully arranged Gather new bases