UVA485 Pascal‘s Triangle of Death大数

Posted 2021-05-19 海岛Blog

In this problem, you are asked to generate Pascal’s Triangle. Pascal’s Triangle is useful in many areas from probability to polynomials to programming contests. It is a triangle of integers with “1” on top and down the sides. Any number in the interior equals the sum of the two numbers above it. For example, here are the first 5 rows of the triangle.

        1
      1 1
    1 2 1
  1 3 3 1
1 4 6 4 1

    In “Pascal’s Triangle of Death,” you are to generate a left justified Pascal’s Triangle. When any number in the triangle is exceeds or equals 1060, your program should finish printing the current row and exit. The output should have each row of the triangle on a separate line with one space between each element.
    The final element of each line should be directly followed by a newline. There is no space after the last number on each line.
Sample Input
There is no input for this problem.
Sample Output
1
1 1
1 2 1
1 3 3 1
1 4 6 4 1
.
.
.

问题链接：UVA485 Pascal’s Triangle of Death
问题简述：（略）
问题分析：大数问题，打印杨辉三角。
程序说明：（略）
参考链接：（略）
题记：（略）

AC的Java语言程序如下：

/* UVA485 Pascal's Triangle of Death */

import java.math.BigInteger;

public class Main {
	public static void main(String args[]) {
		BigInteger a[][] = new BigInteger[300][300];
		a[0][0] = BigInteger.ONE;
		for(int i = 1; i < 300;i++) {
			a[i][0] = BigInteger.ONE;
			for(int j = 1; j < i; j++)
				a[i][j] = a[i - 1][j - 1].add(a[i - 1][j]);
			a[i][i] = BigInteger.ONE;
		}
		BigInteger m = BigInteger.valueOf(10).pow(60);
		m = m.subtract(BigInteger.ONE);
		for(int i = 0; i < 300; i++) {
			int flag = 0;
			for(int j = 0; j <= i; j++) {
				if (m.compareTo(a[i][j]) == -1) flag = 1;
				if (j != 0) System.out.print(" ");
				System.out.print(a[i][j]);
			}
			System.out.println();
			if(flag == 1) break;
		}
	}
}```