C Relational Operators – Compare Values in C

Relational operators in C are used to compare two values or variables. The result of a comparison is either true (1) or false (0), which is useful in decision-making (e.g., in if, while, or for statements).

What Are Relational Operators?

Relational operators help check the relationship between two expressions or variables. They return a Boolean result:

Condition	Result
Condition is true	1
Condition is false	0

List of Relational Operators in C

Operator	Name	Example	Meaning
`==`	Equal to	`a == b`	True if `a` equals `b`
`!=`	Not equal to	`a != b`	True if `a` is not `b`
`>`	Greater than	`a > b`	True if `a` is greater than `b`
`<`	Less than	`a < b`	True if `a` is less than `b`
`>=`	Greater than or equal to	`a >= b`	True if `a` is ≥ `b`
`<=`	Less than or equal to	`a <= b`	True if `a` is ≤ `b`

Example Program Using Relational Operators

#include <stdio.h>

int main() {
    int a = 10, b = 5;

    printf("a == b: %d\n", a == b);   // 0 (false)
    printf("a != b: %d\n", a != b);   // 1 (true)
    printf("a > b: %d\n", a > b);     // 1 (true)
    printf("a < b: %d\n", a < b);     // 0 (false)
    printf("a >= b: %d\n", a >= b);   // 1 (true)
    printf("a <= b: %d\n", a <= b);   // 0 (false)

    return 0;
}

Output:

Use Cases

if (a > b) – Decision-making
while (x <= 100) – Loops
for (i = 0; i != n; i++) – Iteration with condition

Best Practices

Practice	Why?
Always use `==` to compare values	Avoid accidental assignment with `=`
Use parentheses for clarity	Improves readability in conditions
Use relational operators in `if` or `while` loops	Common in control flow

Common Mistakes to Avoid

Mistake	Why it’s Wrong
Using `=` instead of `==`	`=` assigns, doesn’t compare
Not understanding return values	`true` = 1, `false` = 0
Ignoring data types	Comparing `int` to `char` without cast may confuse