Program to find unique minimum in the array...

[surferxo3]

I have the following input and my program is not running: 1 3 2 1 3 7 8

#include<iostream>
#include <cstdlib>

using namespace std;

int main()
{
	int arr[7], min, i=0, j=0;
	
	for(int i=0; i<7; i++)
	{
		cout<<"Enter value at arr["<<i<<"]: ";
		cin>>arr[i];
	}
	
 	min = arr[j];
	for(; i<7; i++)
	{
		if(arr[i] < min)
		{
			min = arr[i];
		}

		if(arr[i] == min)
		{
			min = arr[j+1]; //set min to next value in the array
			i=j+1; //set i to value in the min + 1... program hangs here...
		}
	}

	cout<<endl<<min;
	
	cout<<endl<<endl;
	system("pause");
	return 0;
}

I think my program and the comments reflects my problem clearly... Basically my program tries to do is that when it finds a duplicate min so its set the min value to the next value in the array and set i to the next value pointed out by min so that my loop can start again and find other unique min... But my program hangs... Why?

[NathanOliver]

I belive you need to increment j after line 27 and before line 28. Otherwise you are always starting back at the same place.

[surferxo3]

I tried but still the program hangs... Any other solution?

[L7Sqr]

First, it is not usually a good idea to shadow loop counter variables like you have. A quick read over your code looks like you never reset i after the first loop.

As far as your logic, add a few print statements and you will see what is happening immediately:

arr[0] == min (1 == 1)
arr[2] < min (2 < 3)
arr[2] == min (2 == 2)
arr[2] < min (2 < 3)
arr[2] == min (2 == 2)
arr[2] < min (2 < 3)
arr[2] == min (2 == 2)
arr[2] < min (2 < 3)
arr[2] == min (2 == 2)
...

[WaltP]

For this type of program, the easiest solution is to sort the input then it's an easy matter to find the unique minimum.

[Lerner]

Try not to use multiple variables with the same name within the same program. It's asking for trouble. The only exception might be a simple counting variable used within loops, but then make the variable local to the loop so you don't forget to reset the value to a default value.

If the compiler is compliant, the variable i declared on line 10 overrules the variable i declared on line 8 and goes out of scope on line 14. If it didn't, then the value of the variable i after line 14 would be 7 so the loop on line 17 would never run.

Delete the declaration of i and j from line 8.

Assign the value of arr[0] to min on line 16.

Remove (or comment them out) lines 24 through 28.

Declare j within the loop on line 17 and substitue j for i on lines 17. 19 and 21.

Recompile, debug and run the program. The min value should be 1 if the input is in the sequence originally posted. The program will ignore any duplicate version of min (as can be proven by using a variable to keep track of the index of the element representing min).

[WaltP]

The min value should be 1 if the input is in the sequence originally posted. The program will ignore any duplicate version of min (as can be proven by using a variable to keep track of the index of the element representing min).

Did you miss the term (and description of) unique min? :icon_wink:

[Lerner]

Nope. I didn't miss it, but given your comments, I probably misunderstood what OP was trying to do. My corrections would result in a program that would find the first occurence of the minimum value of the collection. It would not find the minimum value that is also unique within the collection.