# Queries to return the absolute difference between L-th smallest number and the R-th smallest number

Given an array arr[] of N unique elements and Q queries. Every query consists of two integers L and R. The task is to print the absolute difference between the indices of the Lth smallest and the Rth smallest element.

Examples:

Input: arr[] = {1, 5, 4, 2, 8, 6, 7},
que[] = {{2, 5}, {1, 3}, {1, 5}, {3, 6}}
Output:
2
2
5
4
For the first query the second smallest number is 2, which is at index 3
and the 5th smallest number is 6 which is at index 5. Hence the
absolute difference between both such index is 2.

Input: arr[] = {1, 2, 3, 4},
que[] = {{1, 1}, {2, 3}}
Output:
0
1

## Recommended: Please try your approach on {IDE} first, before moving on to the solution.

Approach: The following steps can be followed to solve the above problem.

• Store the elements and their indices in an array of pairs.
• Sort the array according to the first element.
• For every query the answer will be abs(arr[l – 1].second – arr[r – 1].second)

Below is the implementation of the above approach:

 `// C++ implementation of the approach ` `#include ` `using` `namespace` `std; ` ` `  `// Fucntion to return the result ` `// for a particular query ` `int` `answerQuery(pair<``int``, ``int``> arr[], ``int` `l, ``int` `r) ` `{ ` `    ``// Get the difference between the indices of ` `    ``// L-th and the R-th smallest element ` `    ``int` `answer = ``abs``(arr[l - 1].second - arr[r - 1].second); ` ` `  `    ``// Return the answer ` `    ``return` `answer; ` `} ` ` `  `// Function that performs all the queries ` `void` `solveQueries(``int` `a[], ``int` `n, ``int` `q[], ``int` `m) ` `{ ` ` `  `    ``// Store the array numbers ` `    ``// and their indices ` `    ``pair<``int``, ``int``> arr[n]; ` `    ``for` `(``int` `i = 0; i < n; i++) { ` `        ``arr[i].first = a[i]; ` `        ``arr[i].second = i; ` `    ``} ` ` `  `    ``// Sort the array elements ` `    ``sort(arr, arr + n); ` ` `  `    ``// Answer all the queries ` `    ``for` `(``int` `i = 0; i < m; i++) ` `        ``cout << answerQuery(arr, q[i], q[i]) << endl; ` `} ` ` `  `// Driver code ` `int` `main() ` `{ ` `    ``int` `a[] = { 1, 5, 4, 2, 8, 6, 7 }; ` `    ``int` `n = ``sizeof``(a) / ``sizeof``(a); ` `    ``int` `q[] = { { 2, 5 }, { 1, 3 }, { 1, 5 }, { 3, 6 } }; ` `    ``int` `m = ``sizeof``(q) / ``sizeof``(q); ` `    ``solveQueries(a, n, q, m); ` ` `  `    ``return` `0; ` `} `

 `// Java implementation of the approach  ` `import` `java.util.*; ` `import` `java.util.Comparator; ` ` `  `class` `GFG ` `{ ` `     `  `// pair classs ` `static` `class` `pair ` `{ ` `    ``int` `first,second; ` `    ``pair(``int` `f, ``int` `s) ` `    ``{ ` `        ``first = f; ` `        ``second = s; ` `    ``} ` `} ` ` `  `// Fucntion to return the result  ` `// for a particular query  ` `static` `int` `answerQuery(pair arr[], ``int` `l, ``int` `r)  ` `{  ` `    ``// Get the difference between the indices of  ` `    ``// L-th and the R-th smallest element  ` `    ``int` `answer = Math.abs(arr[l - ``1``].second - ` `                        ``arr[r - ``1``].second);  ` ` `  `    ``// Return the answer  ` `    ``return` `answer;  ` `}  ` ` `  `// Function that performs all the queries  ` `static` `void` `solveQueries(``int` `a[], ``int` `n,  ` `                        ``int` `q[][], ``int` `m)  ` `{  ` ` `  `    ``// Store the array numbers  ` `    ``// and their indices  ` `    ``pair arr[] = ``new` `pair[n];  ` `    ``for` `(``int` `i = ``0``; i < n; i++)  ` `    ``{ ` `        ``arr[i] = ``new` `pair(``0``, ``0``); ` `        ``arr[i].first = a[i];  ` `        ``arr[i].second = i;  ` `    ``}  ` `        ``// Sort pair ` `        ``Comparator comp = ``new` `Comparator()  ` `        ``{ ` `             `  `            ``public` `int` `compare(pair e1, pair e2)  ` `            ``{ ` `                ``if``(e1.first < e2.first) ` `                ``{ ` `                    ``return` `-``1``; ` `                ``} ` `                ``else` `if` `(e1.first > e2.first) ` `                ``{ ` `                    ``return` `1``; ` `                ``} ` `                ``else` `                ``{ ` `                    ``return` `0``; ` `                ``} ` `            ``} ` `        ``}; ` `         `  `    ``// Sort the array elements  ` `    ``Arrays.sort(arr,comp);  ` ` `  `    ``// Answer all the queries  ` `    ``for` `(``int` `i = ``0``; i < m; i++)  ` `        ``System.out.println( answerQuery(arr, q[i][``0``], q[i][``1``]));  ` `}  ` ` `  `// Driver code  ` `public` `static` `void` `main(String args[]) ` `{  ` `    ``int` `a[] = { ``1``, ``5``, ``4``, ``2``, ``8``, ``6``, ``7` `};  ` `    ``int` `n = a.length;  ` `    ``int` `q[][] = { { ``2``, ``5` `}, { ``1``, ``3` `}, { ``1``, ``5` `}, { ``3``, ``6` `} };  ` `    ``int` `m = q.length;  ` `    ``solveQueries(a, n, q, m);  ` `}  ` `} ` ` `  `// This code is contributed by Arnab Kundu `

 `# Python 3 implementation of the approach ` ` `  `# Fucntion to return the result ` `# for a particular query ` `def` `answerQuery(arr, l, r): ` `     `  `    ``# Get the difference between the indices  ` `    ``# of L-th and the R-th smallest element ` `    ``answer ``=` `abs``(arr[l ``-` `1``][``1``] ``-`  `                 ``arr[r ``-` `1``][``1``]) ` ` `  `    ``# Return the answer ` `    ``return` `answer ` ` `  `# Function that performs all the queries ` `def` `solveQueries(a, n, q, m): ` `     `  `    ``# Store the array numbers ` `    ``# and their indices ` `    ``arr ``=` `[[``0` `for` `i ``in` `range``(n)]  ` `              ``for` `j ``in` `range``(n)] ` `    ``for` `i ``in` `range``(n): ` `        ``arr[i][``0``] ``=` `a[i] ` `        ``arr[i][``1``] ``=` `i ` ` `  `    ``# Sort the array elements ` `    ``arr.sort(reverse ``=` `False``) ` ` `  `    ``# Answer all the queries ` `    ``for` `i ``in` `range``(m): ` `        ``print``(answerQuery(arr, q[i][``0``],  ` `                               ``q[i][``1``])) ` ` `  `# Driver code ` `if` `__name__ ``=``=` `'__main__'``: ` `    ``a ``=` `[``1``, ``5``, ``4``, ``2``, ``8``, ``6``, ``7``] ` `    ``n ``=` `len``(a) ` `    ``q ``=` `[[``2``, ``5``], [``1``, ``3``],  ` `         ``[``1``, ``5``], [``3``, ``6``]] ` `    ``m ``=` `len``(q) ` `    ``solveQueries(a, n, q, m) ` ` `  `# This code is contributed by ` `# Surendra_Gangwar `

Output:
```2
2
5
4
```

Striver(underscore)79 at Codechef and codeforces D

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Improved By : andrew1234, SURENDRA_GANGWAR

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