convert nested for loop into a nested while loop JAVA

Question

I'm a beginner and I need to convert this "for" loop into a "while" loop.

int s = 0;
int t = 1;

for (int i = 0; i < 5; i++) {
    s = s + i;
    for (int j = i; j > 0; j--) {
        t = t + (j - 1);
    }
    s = s + t;
    System.out.println("T is " + t);
}
System.out.println("S is " + s);

I tried this and it didn't work

int s = 0;
int t = 1;
int i = 0;

while (i < 5)
    i++;
{
    s = s + i;
    int j = i;

    while (j > 0)
        j--;
    {
        t = t + (j - 1);
    }
    s = s + t;
    System.out.println("T is " + t);
}
System.out.println("S is " + s);

the output was T=0 and S = 5 when it should read

T is 1
T is 1
T is 2
T is 5
T is 11
S is 30

thanks

Answer 1

int s = 0;
int t = 1;
int i = 0;

while (i < 5) 
{
    s = s + i;
    int j = i;

    while (j > 0) 
    {
        t = t + (j-1);
        j--;
    }
    i++;
    s = s + t;
    System.out.println("T is " + t);
}
System.out.println("S is " + s);

You should look into the syntax more carefully. Otherwise you were executing the blocks single time.

Earlier you were running this

while (i < 5) 
    i++;

Which is basically executing the loop 5 times and after the end of the loop i gets the value of 5.

After that we are running the block and we encounter the while loop again.

while (j > 0) 
        j--;

It executes 5 times again. So it would be j=0 after this loop ends.

So you end up with t=0 and s=5 . That's it.

Answer 2

The i++; should be inside the loop's brackets, not placed before. Same with j .

while (i < 5) 
{
    s = s + i;
    int j = i;

    while (j > 0) 
    {
        t = t + (j-1);
        j--; // j needs to be incremented here
    }
    s = s + t;
    i++; // i needs to be incremented here
}

As it currently is, you have a loop where the only statement is i++; , and then the rest of the code, which is in its own code block (or local scope), is executed only once.