Nested for loop with examples

Question

I can't understand how the flow of nested loops are when I saw several * print programs

Answer 1

for (int i = 1; i <= 4; i++) {
for (int k = 1; k <= 3; k++) {
// some code
}
}
i, k values on following iterations:
i = 1, k = 1
i = 1, k = 2
i = 1, k = 3
i = 2, k = 1
i = 2, k = 2
i = 2, k = 3
i = 3, k = 1
i = 3, k = 2
i = 3, k = 3
i = 4, k = 1
i = 4, k = 2
i = 4, k = 3
In other words, whole inner loop will be executed for each iteration of outer loop.
If outer loop runs n times, inner loop runs m times, then code in the inner loop will be executed n*m times.

Answer 2

no bro it didn't meet my expectations I learned nothing from your comment

Answer 3

Perhaps, due to lack of the basic programming knowledge: syntax, terms, keywords. I personally can not explain it in other words in a simple way.
My advice for you is to finish your Java course on SoloLearn at first.
Try to run this code, maybe it helps:
for (int i = 1; i <= 4; i++) {
for (int k = 1; k <= 3; k++) {
System.out.print("i = " + i); // prints out i value
System.out.println(", k = " + k); //prints out k value
}
}