杨辉三角的变形（数学）

题目

import java.util.Scanner;public class Main {public static void main(String[] args) {
//		1
//		1 1 1
//		1 2 3 2 1
//		1 3 6 7 6 3 1
//		1 4 10 16 19 16 10 4 1Scanner sc = new Scanner(System.in);int n = sc.nextInt();int[][] res = new int[n+1][2*n];for(int i=1;i<=n;i++) {res[i][1] = 1;res[i][2*i-1] = 1;}//第二列for(int i=2;i<=n;i++) {res[i][2] = res[i-1][1]+res[i-1][2];}//大于等于第三列for(int i=3;i<=n;i++) {for(int j=3;j<=(2*n-1);j++) {res[i][j] = res[i-1][j-2]+res[i-1][j-1]+res[i-1][j];}}for(int j=1;j<=(2*n-1);j++) {if(res[n][j]%2 == 0) {System.out.println(j);return ;}}System.out.println(-1);sc.close();}
}

import java.util.Scanner;public class Main {public static void main(String[] args) {
//      1
//      1 1 1
//      1 2 3 2 1
//      1 3 6 7 6 3 1
//      1 4 10 16 19 16 10 4 1Scanner sc = new Scanner(System.in);int n = sc.nextInt();int[][] res = new int[n][2 * (n - 1) + 1];res[0][0] = 1;for (int i = 1; i < n; i++) {res[i][0] = 1;res[i][2 * i] = 1;}//第二列for (int i = 1; i < n; i++) {res[i][1] = res[i - 1][0] + res[i - 1][1];}//大于等于第三列for (int i = 2; i < n; i++) {for (int j = 2; j < 2 * (n - 1) + 1; j++) {res[i][j] = res[i - 1][j - 2] + res[i - 1][j - 1] + res[i - 1][j];}}for (int j = 0; j < 2 * (n - 1) + 1; j++) {if (res[n - 1][j] % 2 == 0) {System.out.println(j + 1);return ;}}System.out.println(-1);
//      for(int i=0;i<n;i++) {
//          for(int j=0;j<(2*(n-1)+1);j++){
//              System.out.print(res[i][j]);
//          }
//          System.out.println();
//      }sc.close();}
}

下标为0或者1都不能通过全部样例

import java.util.Scanner;public class Main {public static void main(String[] args) {Scanner in = new Scanner(System.in);int num = in.nextInt();if(num == 1 || num == 2){System.out.println(-1);}else if(num % 4 == 1 || num % 4 == 3){System.out.println(2);}else if(num % 4 == 0){System.out.println(3);}else if(num % 4 == 2){System.out.println(4);}}
}