Trace the output for the following C program with post-decrement in the condition and multiple loops: #include<stdio.h> int main() { int i = 5; while (i-- >= 0) printf("%d,", i); i = 5; printf("\n"); while (i-- >= 0) printf("%i,", i); while (i-- >= 0) printf("%d,", i); return 0; }

Introduction / Context:
This problem focuses on how i-- behaves in a loop condition and how the variable's value changes before the body executes. It also contrasts two loops separated by a reset and a newline, then shows that a final loop may not execute at all.

Given Data / Assumptions:

• Initial i = 5.
• Condition i-- >= 0 compares first, then decrements.
• The body prints the current (already decremented) i.

Concept / Approach:
When the condition is i-- >= 0, the comparison uses the old value of i, then i is decremented before entering the body. Consequently, the printed sequence is one less than the value checked in the condition. The loop runs while the old value is at least 0, producing a sequence down to −1 in the output.

Step-by-Step Solution:

Verification / Alternative check:
Change the condition to --i >= 0 or i >= 0 with a separate decrement to see how the printed values shift.

Why Other Options Are Wrong:

Common Pitfalls:
Forgetting the difference between pre- and post-decrement; assuming %i and %d differ for int (they do not).

Final Answer:
4, 3, 2, 1, 0, -1 4, 3, 2, 1, 0, -1.