For Loop Part 1

Part of the Fundamentals section of Coddy's C++ journey. Lesson 42 of 74.

Sometimes when programming, it's necessary to perform the same or almost the same operation a couple of times.

To prevent writing the same thing over and over again, we can use Loops.

The for loop has the following syntax:

for (initialization; condition; update) {
    code
}

The initialization, condition and update determine what is the start value and what is the end value.

For example, loop from 0 to 5 (not including):

for (int i = 0; i < 5; i++) {
    std::cout << i << std::endl;
}

It will execute the print statement 5 times:

In this loop the starting value is 0 (like int i = 0), the condition checks if the loop should continue (like i < 5), and the update changes the value after each iteration (like i++).

Loops have many use cases. For example, let's sum all the numbers from 1 to 100:

int sum_numbers = 0;
for (int i = 1; i <= 100; i++) {
    sum_numbers += i;
}
std::cout << sum_numbers;

This will first loop through all numbers between 1 and 100 (including 100 because of <= sign) and sum all of them, then it will print the sum_numbers variable

Challenge

Beginner

Read an integer n (the starter code already does this). Use a for loop to print "Hello Coddy: " and the i value for every number from 3 to n, both included.

For example, if n is 6, the output is:

Hello Coddy: 3
Hello Coddy: 4
Hello Coddy: 5
Hello Coddy: 6

If n is 27, the loop prints 25 lines, from Hello Coddy: 3 to Hello Coddy: 27.

Try it yourself

#include <iostream>

int main() {
    int n;
    std::cin >> n;
    // Write your code below
    
    return 0;
}

Test yourself

This lesson includes a short quiz. Start the lesson to answer it and track your progress.

All lessons in Fundamentals

Practice on your own: Online C++ compiler