Thread: Don't clearly understand the function of ".nextLine()" & a comparison of two codes

The function of the code is as below:
Classify one's age and,
if sb is over 18 years old, then compare his/her favorite food with "pizza".

package practice;
 
import java.util.Scanner;
 
public class Main {
    public static void main(String[] args) {
        System.out.println("Type your age here:");
        Scanner sc=new Scanner(System.in);
        int age=sc.nextInt();    //this is the difference between two codes
        if (age>=18) {
            System.out.println("Type your favourite food here: ");
            String food = sc.nextLine();
 
            if (food.equals("pizza")) {
                System.out.println("Mine too!");
            }
            else {
                System.out.println("not mine!");
            }
        }
        else if(age>=13){
            System.out.println("You are a teenager");
        }
        else{
            System.out.println("You are a child");
        }
 
    }}

The code above can't fulfill my purpose.

package practice;
 
import java.util.Scanner;
 
public class Main {
    public static void main(String[] args) {
        System.out.println("Type your age here:");
        Scanner sc=new Scanner(System.in);
        String s=sc.nextLine();
        int age=Integer.parseInt(s);  //This is the difference between two codes
        if (age>=18) {
            System.out.println("Type your favourite food here: ");
            String food = sc.nextLine();
 
            if (food.equals("pizza")) {
                System.out.println("Mine too!");
            }
            else {
                System.out.println("not mine!");
            }
        }
        else if(age>=13){
            System.out.println("You are a teenager");
        }
        else{
            System.out.println("You are a child");
        }
 
    }}