If...Else

Relax. We'll talk through this in plain words — no textbook voice.

if...else is used to run different code blocks depending on a condition. Checking login access, assigning a grade based on a score, checking whether stock is available — they all follow this same logic pattern.

#include <stdio.h>

int main() {
  int score = 72;

  if (score >= 80) {
    printf("Grade A");
  } else if (score >= 60) {
    printf("Grade B");
  } else {
    printf("Try again");
  }
  return 0;
}

The program checks the conditions from top to bottom. score >= 80 is false, so it moves on to check the next condition, and score >= 60 is true, so Grade B gets printed.

You should see

Grade B

Info

Put the stricter condition first. In grade logic, score >= 60 if you check this first, even students scoring above 80 could end up landing in B.

Easy traps

Getting the order of your else if chain wrong causes logic bugs. Watch out — the compiler won't throw an error, but the result can still come out wrong.