I've tried the following code but it gives a wrong output .....can somebody help me? Test case will be 3001213 n output is 300

Question

#include <iostream>
using namespace std;
int main() {
int num;
cin>>num;
int len= to_string(num).length();
int arr[10],lnum=0,max=0;
for (int i =len-1;i>=0;i--)
{
arr[i] = num%10;
num =num/10; //to convert int into array
}
for (int i=0;i<len-2;i++)
{
if (arr[i] >arr[i+1])
lnum = arr[i]*100+arr[i+1]*10+arr[i];
if (lnum>max)
max= lnum;
}
cout<<max;
return 0;
}

Answer 1

Complete task Description?

Answer 2

Find largest 3 digit number within a numerical string
Input
3001213
Output
300
Input
6478434
Output
843

Answer 3

you have two mistakes in your logic:

1) no need to check if (arr[i]>arr[i+1])

2) using twice arr[i] in lnum computation (instead/lacks of arr[i+2]):

lnum = arr[i]*100+arr[i+1]*10+arr[i+2];

https://code.sololearn.com/c7jqaoUJt141/?ref=app

anyway, are you sure you must take input as number rather as string? (what if input overflow int capacity?)... as task say "numerical string" ^^