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[alielsaadi]

Can someone help me understand how we got the result with this code?

 #include <iostream>
#include <ctime>
#include <cstdlib>
#include <iomanip>
using namespace std;

void main()
{
	int a[4] = { 10, 20, 30, 40 };
	int i = 0;
	int j = 4;
	while (i++ < 4)
	{
		j = i;
		cout << a[i] << endl;
		while (j-->0)
			cout << i << " ";
	}


     system("pause");
}

[Esslercuffi]

since you increment i in the while( i++ < 4 ) line, you never output element 0.

[alielsaadi]

I get that part. i dont get line 16 and 17.

[PCrumley48]

What is the original problem? What is the objective of the program?

[alielsaadi]

no problem and no objective.
im just trying to find out how we get the numbers that the program outputs.

[Esslercuffi]

in line 16: j-- is the postfix decrement operator. which means it won't be decremented until after the comparison is made. try it with the prefix decrement while( --j > 0 ) and see if that's what you were expecting.