In this article we will learn how to print Pascal's Triangle based on User Input. So Program will basically ask User to enter the number of rows/lines upto which the pascal triangle will be printed and Program will display the Pascal Triangle.
Java Program for Pascal Triangle:
import java.util.Scanner;
public class ScannerTest {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.print("Enter the number of rows: ");
int rows = sc.nextInt();
System.out.println("Pascal Triangle for row: "+rows);
printTriangle(rows);
sc.close();
}
public static void printTriangle(int n) {
for (int i = 0; i < n; i++) {
for (int k = 0; k < n - i; k++) {
System.out.print(" "); // print space for display like triangle
}
for (int j = 0; j <= i; j++) {
System.out.print(pascal(i, j) + " ");
}
System.out.println();
}
}
public static int pascal(int i, int j) {
if (j == 0 || j == i) {
return 1;
} else {
return pascal(i - 1, j - 1) + pascal(i - 1, j);
}
}
}
Output:
Enter the number of rows: 5
Pascal Triangle for row: 5
1
1 1
1 2 1
1 3 3 1
1 4 6 4 1