HackerRank #1 #for loop

Input Format

You will be given two positive integers, a and b(a<=b), separated by a newline.

Output Format

For each integer in the inclusive interval :

If 1 <= n <= 9, then print the English representation of it in lowercase. That is “one” for , “two” for , and so on. Else if n>9 and it is an even number, then print “even”.
Else if n>9 and it is an odd number, then print “odd”.

Sample Input

8
11
Sample Output

eight
nine
even
odd

#include <iostream>
#include <cstdio>
using namespace std;

int main() {
    // Complete the code.
    int a;
    int b;
    cin>>a>>b;
    
    for(int i = a; i <= b; i++){
        if(i <=9 ){
            switch(i){
                case 1:
                    cout<<"one";
                    break;
                case 2:
                    cout<<"two";
                    break;
                case 3:
                    cout<<"three";
                    break;
                case 4:
                    cout<<"four";
                    break;
                case 5:
                    cout<<"five";
                    break;
                case 6:
                    cout<<"six";
                    break;
                case 7:
                    cout<<"seven";
                    break;
                case 8:
                    cout<<"eight";
                    break;
                case 9:
                    cout<<"nine";
                    break;
            }
        }else{
                if(i % 2 == 0){
                    cout<<"even";
                }else{
                    cout<<"odd";
                }
            }
            cout<<endl;
    }
    
   
    return 0;
}

c++14 version

Explaining the Code to the Audience of GetCode

This C++ program solves a very common problem: printing the name of the numbers-for numbers between 1 and 9-and for numbers larger than 9, it prints whether the number is odd or even. Now, let’s go through the code in detail to see the logical explanation of it.

#include <iostream>:  This is used for input and output operations, namely cin and cout.
#include <cstdio>:  For C-style input and output. Not used in this code. Probably out of habit when writing code.

int a;
int b;
int a and int b:  Variable to store the range of number input provided by the user.

cin >> a >> b;
Purpose: Takes input from user two integers a and b. Represents the start and end of a range, inclusive. Iteration Through Range.

for(int i = a; i <= b; i++) {
Purpose: iterates through every number between a and b. Handling Numbers <= 9:

if (i <= 9) {
switch (i) {
case 1: cout << “one”; break;
case 2: cout << “two”; break;
//. other cases
}
}

For any digit from 1 to 9, a switch is used that prints their name in English – one, two etc.
Handling Numbers > 9:


} else {
if (i % 2 == 0) {
cout << “even”;
} else {
cout << “odd”;
}
}
i % 2 == 0 Checks whether the number is even.
If true, prints “even”.
Else, prints “odd”.
-formatting Output:

cout << endl;
Displays result from a new line every time.
End

return 0;
Indicates that the program was executed successfully.
Sample Input and Output

Input→Explanation→Output
1 5 Numbers 1 to 5 are within 1-9. one
two
three
four
five
8 11 , 8 is in 1-9, others are odd/even. eight
odd
even
odd

Key Features:

Simple Logic: Combines a for loop, switch statement, and conditional checks.

Readable Output: Ensures clarity by mapping names and distinguishing odd/even numbers.

Versatile Range: Works for any positive range [a, b] with a <= b.
Why is this Code Effective?
Beginner-Friendly: Uses basic concepts like loops, conditionals, and switches.
Logical Flow: Covers all cases (1-9, odd/even) systematically.
Efficiency: The range is processed within one loop.

This is a HackerRank problem. I have taken this question from: https://www.hackerrank.com/challenges/c-tutorial-for-loop/problem?isFullScreen=true