Find element using minimum segments in Seven Segment Display

A Seven Segment Display can be used to display numbers. Given an array of n natural numbers. The task is to find the number in the array which is using minimum segments to display number. If multiple numbers have a minimum number of segments, output the number having the smallest index.

Examples :

Input : arr[] = { 1, 2, 3, 4, 5 }.
Output : 1
1 uses on 2 segments to display.

Input : arr[] = { 489, 206, 745, 123, 756 }.
Output : 745

Precompute the number of segment used by digits from 0 to 9 and store it. Now for each element of the array sum the number of segment used by each digit. Then find the element which is using the minimum number of segments.

The number of segment used by digit: 
0 -> 6 
1 -> 2 
2 -> 5 
3 -> 5 
4 -> 4 
5 -> 5 
6 -> 6 
7 -> 3 
8 -> 7 
9 -> 6

Below is the implementation of this approach: 

C++

// C++ program to find minimum number of segments
// required
#include<bits/stdc++.h>
using namespace std;

// Precomputed values of segment used by digit 0 to 9.
const int seg[10] = { 6, 2, 5, 5, 4, 5, 6, 3, 7, 6};

// Return the number of segments used by x.
int computeSegment(int x)
{
    if (x == 0)
        return seg[0];

    int count = 0;

    // Finding sum of the segment used by
    // each digit of a number.
    while (x)
    {
        count += seg[x%10];
        x /= 10;
    }

    return count;
}

int elementMinSegment(int arr[], int n)
{
    // Initialising the minimum segment and minimum
    // number index.
    int minseg = computeSegment(arr[0]);
    int minindex = 0;

    // Finding and comparing segment used
    // by each number arr[i].
    for (int i = 1; i < n; i++)
    {
        int temp = computeSegment(arr[i]);

        // If arr[i] used less segment then update
        // minimum segment and minimum number.
        if (temp < minseg)
        {
            minseg   = temp;
            minindex = i;
        }
    }

    return arr[minindex];
}

// Driven Program
int main()
{
    int arr[] = {489, 206, 745, 123, 756};
    int n = sizeof(arr)/sizeof(arr[0]);
    cout << elementMinSegment(arr, n) << endl;
    return 0;
}

Java

// Java program to find minimum
// number of segments required
import java.io.*;

class GFG {

// Precomputed values of segment
// used by digit 0 to 9.
static int []seg = { 6, 2, 5, 5, 4, 5, 6, 3, 7, 6};

// Return the number of segments used by x.
static int computeSegment(int x)
{
    if (x == 0)
        return seg[0];

    int count = 0;

    // Finding sum of the segment used by
    // each digit of a number.
    while (x > 0)
    {
        count += seg[x % 10];
        x /= 10;
    }

    return count;
}

static int elementMinSegment(int []arr, int n)
{
    // Initialising the minimum segment
    // and minimum number index.
    int minseg = computeSegment(arr[0]);
    int minindex = 0;

    // Finding and comparing segment used
    // by each number arr[i].
    for (int i = 1; i < n; i++)
    {
        int temp = computeSegment(arr[i]);

        // If arr[i] used less segment then update
        // minimum segment and minimum number.
        if (temp < minseg)
        {
            minseg = temp;
            minindex = i;
        }
    }

    return arr[minindex];
}

    // Driver program
    static public void main (String[] args)
    {
       int []arr = {489, 206, 745, 123, 756};
       int n = arr.length;
       System.out.println(elementMinSegment(arr, n));
    }
}

//This code is contributed by vt_m.

Python3

# Python implementation of
# the above approach

# Precomputed values of segment
# used by digit 0 to 9.
seg = [6, 2, 5, 5, 4,
       5, 6, 3, 7, 6]

# Return the number of
# segments used by x.
def computeSegment(x):
    if(x == 0):
        return seg[0]

    count = 0

    # Finding sum of the segment
    # used by each digit of a number.
    while(x):
        count += seg[x % 10]
        x = x // 10

    return count

# function to return minimum sum index
def elementMinSegment(arr, n):

    # Initialising the minimum
    # segment and minimum number index.
    minseg = computeSegment(arr[0])
    minindex = 0

    # Finding and comparing segment
    # used by each number arr[i].
    for i in range(1, n):
        temp = computeSegment(arr[i])

        # If arr[i] used less segment
        # then update minimum segment
        # and minimum number.
        if(temp < minseg):

            minseg = temp
            minindex = i

    return arr[minindex]

# Driver Code
arr = [489, 206, 745, 123, 756]
n = len(arr)

# function print required answer
print(elementMinSegment(arr, n))

# This code is contributed by
# Sanjit_Prasad

C#

// C# program to find minimum
// number of segments required
using System;

class GFG{

// Precomputed values of segment
// used by digit 0 to 9.
static int []seg = new int[10]{ 6, 2, 5, 5, 4,
                               5, 6, 3, 7, 6};

// Return the number of segments used by x.
static int computeSegment(int x)
{
    if (x == 0)
        return seg[0];

    int count = 0;

    // Finding sum of the segment used by
    // each digit of a number.
    while (x > 0)
    {
        count += seg[x % 10];
        x /= 10;
    }

    return count;
}

static int elementMinSegment(int []arr, int n)
{
    // Initialising the minimum segment
    // and minimum number index.
    int minseg = computeSegment(arr[0]);
    int minindex = 0;

    // Finding and comparing segment used
    // by each number arr[i].
    for (int i = 1; i < n; i++)
    {
        int temp = computeSegment(arr[i]);

        // If arr[i] used less segment then update
        // minimum segment and minimum number.
        if (temp < minseg)
        {
            minseg = temp;
            minindex = i;
        }
    }

    return arr[minindex];
}

    // Driver program
    static public void Main()
    {
       int []arr = {489, 206, 745, 123, 756};
       int n = arr.Length;
       Console.WriteLine(elementMinSegment(arr, n));
    }
}

//This code is contributed by vt_m.

PHP

<?php
// PHP program to find minimum
// number of segments required

// Precomputed values of segment
// used by digit 0 to 9.

$seg = array(6, 2, 5, 5, 4,
             5, 6, 3, 7, 6);

// Return the number of
// segments used by x.
function computeSegment($x)
{
    global $seg;
    if ($x == 0)
        return $seg[0];

    $count = 0;

    // Finding sum of the segment
    // used by each digit of a number.
    while ($x)
    {
        $count += $seg[$x % 10];
        $x = (int)$x / 10;
    }

    return $count;
}

function elementMinSegment($arr, $n)
{
    // Initialising the minimum segment
    // and minimum number index.
    $minseg = computeSegment($arr[0]);
    $minindex = 0;

    // Finding and comparing segment
    // used by each number arr[i].
    for ($i = 1; $i < $n; $i++)
    {
        $temp = computeSegment($arr[$i]);

        // If arr[i] used less segment
        // then update minimum segment
        // and minimum number.
        if ($temp < $minseg)
        {
            $minseg = $temp;
            $minindex = $i;
        }
    }

    return $arr[$minindex];
}

// Driver Code
$arr = array (489, 206, 745, 123, 756);
$n = sizeof($arr);
echo elementMinSegment($arr, $n) ,"\n";

// This code is contributed by ajit
?>

Javascript

<script>

// Javascript program to find minimum
// number of segments required

// Precomputed values of segment
// used by digit 0 to 9.
let seg = [ 6, 2, 5, 5, 4, 5, 6, 3, 7, 6];

// Return the number of segments used by x.
function computeSegment(x)
{
    if (x == 0)
        return seg[0];

    let count = 0;

    // Finding sum of the segment used by
    // each digit of a number.
    while (x > 0)
    {
        count += seg[x % 10];
        x = parseInt(x / 10, 10);
    }
    return count;
}

function elementMinSegment(arr, n)
{

    // Initialising the minimum segment
    // and minimum number index.
    let minseg = computeSegment(arr[0]);
    let minindex = 0;

    // Finding and comparing segment used
    // by each number arr[i].
    for(let i = 1; i < n; i++)
    {
        let temp = computeSegment(arr[i]);

        // If arr[i] used less segment then update
        // minimum segment and minimum number.
        if (temp < minseg)
        {
            minseg = temp;
            minindex = i;
        }
    }
    return arr[minindex];
}

// Driver code
let arr = [ 489, 206, 745, 123, 756 ];
let n = arr.length;

document.write(elementMinSegment(arr, n));

// This code is contributed by divyesh072019

</script>

Output

745

Time Complexity: O(n * log₁₀n)
Auxiliary Space: O(10)