Tour

Walter White is on a tour to sell meth. There are N cities.

Each city has a id between 1 and N (both inclusive).

You are given a cost matrix.

In cost matrix, the $jth$ element in the $ith$ row denotes the cost of travelling between cities with $id$ i and j.

$cost[i][j]=cost[j][i]$ and $cost[i][i]=0$

Given the path taken by Walter, print the cost of traveling.

Walter is at the city with $id$ 1 right now.

Example:

Input: n = 3, str = {"delhi", "bengaluru", "hyderabad"}, arr = {{0, 10, 20}, {10, 0, 55}, {20, 55, 0}}, q = 4, queries = {"bengaluru", "delhi", "hyderabad", "bengaluru"}
Output: 95

Approach

C++

#include <bits/stdc++.h>
using namespace std;

long long tour(long long n, vector<string> str,
               vector<vector<long long>> arr, long long q,
               vector<string> queries)
{

    map<string, long long> mp;

    for (long long i = 0; i < n; i++)
    {

        mp[str[i]] = i;
    }

    long long i = 0, j = 0;
    long long ans = 0;

    for (long long k = 0; k < q; k++)
    {
        string s = queries[k];
        j = mp[s];
        ans += arr[i][j];
        i = j;
    }

    return ans;
}

int main()
{
    long long n = 3;

    vector<string> str = {"delhi",
                          "bengaluru",
                          "hyderabad"};

    vector<vector<long long>> arr = {{0, 10, 20},
                                     {10, 0, 55},
                                     {20, 55, 0}};

    long long q = 4;

    vector<string> queries = {"bengaluru",
                              "delhi",
                              "hyderabad",
                              "bengaluru"};
    cout << tour(n, str, arr, q, queries) << "\n";

    return 0;
}