C++ Conditions

The if Statement

Use if to run code only when a condition is true:

if (condition) {
    // code runs when condition is true
}

#include <iostream>
using namespace std;

int main() {
    int score = 85;

    if (score >= 90) {
        cout << "Grade: A" << endl;
    }
    if (score >= 80) {
        cout << "Grade: B" << endl;
    }
    return 0;
}

Output:

Grade: B

else and else if

#include <iostream>
using namespace std;

int main() {
    int score;
    cout << "Enter score: "; cin >> score;

    if (score >= 90) {
        cout << "A — Excellent!" << endl;
    } else if (score >= 80) {
        cout << "B — Good" << endl;
    } else if (score >= 70) {
        cout << "C — Average" << endl;
    } else if (score >= 60) {
        cout << "D — Below Average" << endl;
    } else {
        cout << "F — Fail" << endl;
    }
    return 0;
}

Ternary Operator

A shortcut for simple if-else in one line:

// Syntax: condition ? valueIfTrue : valueIfFalse
int age = 20;
string status = (age >= 18) ? "Adult" : "Minor";
cout << status;   // Adult

#include <iostream>
using namespace std;

int main() {
    int temp;
    cout << "Enter temperature (C): "; cin >> temp;

    if (temp > 30) {
        cout << "Hot" << endl;
    } else if (temp >= 15) {
        cout << "Warm" << endl;
    } else {
        cout << "Cold" << endl;
    }
    return 0;
}

Summary

• if executes a block when the condition is true.
• else if adds additional conditions.
• else runs when no conditions matched.
• The ternary operator ?: is a compact one-line if-else.