Vpropel VIT | POD | 14/05/2020 | Train routes | 44

Question(train_routes).txt

Train routes
A train stops on n stations numbered from 0 to n - 1 that form a circle. 
We know the distance between all pairs of neighboring stations where distance[i] is the distance between the station number
i and (i + 1) % n.
The train goes along both directions i.e. clockwise and counterclockwise.

Return the shortest distance between the given start and destination stations.

Example:-

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

Output: 4

Explanation: Distance between 0 and 3 is 6 or 4, minimum is 4.

Input format:-

Number of stations(n)

Next n lines – distances

Starting station

Destination station

Output format:-

Minimum distance between start and destination

Rank.txt

41	19BCE1082	G O NARENDRA
42	19BCE2643	SANDESH DHUNGANA
43	19BCE0345	ANURAG PANDEY
44	19BCI0016	CHIRANJEET SINGH
45	19BCE1773	PRIYA
46	19BCI0083	NAMIT GUPTA
47	19MIS0308	U A ABHILASH

train_routes.c

#include<stdio.h>
int min(int a,int b)
{
    return (a<b)?a:b;
}
int Mindist(int arr[],int n,int st,int end)
{
    int tot[2]={0,0};
    int i=st;
    while(i!=end)
    {
        tot[0]+=arr[i];
        i=(i+1)%n;
    }
    while(i!=st)
    {
        tot[1]+=arr[i];
        i=(i+1)%n;
    }
    return min(tot[0],tot[1]);
}
int main()
{
    int n;
    scanf("%d",&n);
    int distance[n];
    for(int i=0;i<n;i++)
    {
        scanf("%d",&distance[i]);
    }
    int start,end;
    scanf("%d%d",&start,&end);
    printf("%d",Mindist(distance,n,start,end));
    return 0;
}

train_routes.cpp

// O(n)
#include<iostream>
#include<algorithm>
int Mindist(int arr[],int n,int st,int end)
{
    int tot[2]={0};
    int i=st;
    while(i!=end)
    {
        tot[0]+=arr[i];
        i=(i+1)%n;
    }
    while(i!=st)
    {
        tot[1]+=arr[i];
        i=(i+1)%n;
    }
    return std::min(tot[0],tot[1]);
}
int main()
{
    int n;
    std::cin>>n;
    int distance[n];
    for(int i=0;i<n;i++)
    {
        std::cin>>distance[i];
    }
    int start,end;
    std::cin>>start>>end;
    std::cout<<Mindist(distance,n,start,end);
}

train_routes.java

import java.util.Scanner;
class MDist
{
   private static int min(int a,int b)
    {
        return (a<b)?a:b;
    }
    public static int Mindist(int arr[],int n,int st,int end)
    {
        int tot[]=new int[2];
        int i=st;
        while(i!=end)
        {
            tot[0]+=arr[i];
            i=(i+1)%n;
        }
        while(i!=st)
        {
            tot[1]+=arr[i];
            i=(i+1)%n;
        }
        return min(tot[0],tot[1]);
    }
}

public class Main
{
    public static void main(String[] args)
    {
        Scanner s=new Scanner(System.in);
        int n=s.nextInt();
        int stations[]=new int[n];
        for(int i=0;i<n;i++)
            stations[i]=s.nextInt();
        int start=s.nextInt();
        int end=s.nextInt();
        System.out.print(MDist.Mindist(stations,n,start,end));
    }
}

train_routes.py

n=int(input())
l=[]
for i in range(n):
    l.append(int(input()))
start=int(input())
end=int(input())
tot=[0,0]
i=start
while i!=end:
    tot[0]+=l[i]
    i=(i+1)%n
while i!=start:
    tot[1]+=l[i]
    i=(i+1)%n
print(min(tot[0],tot[1]))