How do I find the second largest number when I input an array of numbers?

general
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1

For example, if i enter 5 values, 5,10,3,5,7,8
I want a code to find the second largest value
I dunno how to do it
I’m new to this :slight_smile:
Don’t h8 m8

2

if you are beginner then first try to find the largest of all the elements…(it can be done if you know how to use loops.) after this you can remove this(largest) element(it’s index) and then run the same code on the remaining … :slight_smile:

3

You can sort the array first for ex

your array after getting sorted will look like this

3 5 5 7 8 10

so, you know that last element is the largest is 10

set the int max value equals to (max = array[size-1])

and then make a loop which will start from the end and go until it finds a different value than the max, that will be our second largest

for(int i = size-1; i>=0;i–)

{

if(array[i]!=max)

{

secondLargest = array[i];

break;

}

}
this will give you the second largest number

and as pk301 mentioned that you can find the largest number but you don’t have to delete the value just keep the track the index of the largest element and then loop through one more time and check

if(j(which was the index of largest)!=i)
and array[i] is largest in the array after the maximum.

4

But what should I do after that? The syntax is confusing to me. Thanks for the reply though!!

5

Is there a way to do it without sorting to keep it as efficient as possible?
I’ll try this to see if it works. Thanks! meow

6

It’s showing a compiling error…

7

try this http://www.geeksforgeeks.org/find-second-largest-element-array/ Hope this helps :slight_smile:

8

It can be done with single traversal only :slight_smile:

9

IT’S NOT WORKING AHHHHH

10

Show me your code

11

ask me if you have any questions

      #include <iostream>

      using namespace std;

  int main()
 {
int size;
cin >> size;
int array[size];

for(int i = 0;i<size;i++)
    cin >> array[i];


int largest = array[0];
int index = 0;
int secondLargest = array[0];
for(int i = 1;i<size;i++)
{
    if(largest<array[i])
    {
        index = i;
        largest = array[i];
    }

    if(i!=index)
          {
        if(secondLargest<array[i])
            secondLargest = array[i];
    }
}

cout << "second largest is " <<  secondLargest << endl;
return 0;

}

12

Dont h8 m8 .

13

I want one where i input a random set of numbers myself and it shows the second highest num :frowning:

14

its working but the result isn’t coming correctly…

#include
using namespace std;

int main()
{
int i = 0;

int run[6], second_max;
cout << "Enter 6 numbers";
for (int i = 0; i < 6; i++)
cin >> run[i];
second_max = 0;
for (int i = 0; i < 6; i++);
{
	int second_max = i;
}

cout << second_max << "send second max num of"<< run[second_max];

void waitforuserinput();
char exitchar;
cin >> exitchar;

}

15

array = [] // some array

// first is the maximum of the arrray

first = max(array)

f_time=False ;
second= 0

// iterating to find the next max

for i in range(len(array)):

if second < array[i] and array[i] != first:

second = array[i]

elif array[i] == first :

// in case there more than one elemnt that is the max

if f _time :

second = array[i]

else :

f _time= True

// second has the second max in the array

16

@crash21499 it is working

17

@beginner_1111 show me

18

it isn’t working…

19

bro just take the input
Ok let me edit the solution for you

20

Okay I edited the solution first enter the size of the array and then your random set of numbers