Relational operators in Rust

Introduction

Relational operators help us compare two values to see how they relate, like if one is bigger or smaller than the other.

Checking if a number is greater than another to decide what to do next.

Comparing ages to see who is older.

Finding out if two values are equal before continuing a task.

Making sure a score is less than a limit before allowing a player to continue.

Deciding if a temperature is within a safe range.

Syntax

Rust

value1 < value2
value1 > value2
value1 <= value2
value1 >= value2
value1 == value2
value1 != value2

Use == to check if two values are equal.

Use != to check if two values are not equal.

Examples

This checks if a is less than b. It is true because 5 is less than 10.

Rust

let a = 5;
let b = 10;
let result = a < b; // true

This checks if x is equal to y. It is true because both are 7.

Rust

let x = 7;
let y = 7;
let result = x == y; // true

This checks if m is not equal to n. It is true because 3 is not 8.

Rust

let m = 3;
let n = 8;
let result = m != n; // true

Sample Program

This program checks if a person is old enough to enter by comparing age with limit. It also prints if the score is passing by comparing score with passing_score.

Rust

fn main() {
    let age = 20;
    let limit = 18;

    if age >= limit {
        println!("You are allowed to enter.");
    } else {
        println!("You are not allowed to enter.");
    }

    let score = 85;
    let passing_score = 60;

    println!("Did you pass? {}", score >= passing_score);
}

Important Notes

Relational operators always return a boolean: true or false.

Use parentheses to group comparisons if combining with other operators.

Summary

Relational operators compare two values and return true or false.

Common operators: <, >, <=, >=, ==, !=.

They help make decisions in your program based on value comparisons.