題目描述:
本題要求將給定的 N 個正整數按非遞增的順序,填入“螺旋矩陣”。所謂“螺旋矩陣”,是指從左上角第 1 個格子開始,按順時針螺旋方向填充。要求矩陣的規模爲 m 行 n 列,滿足條件:m×n 等於 N;m≥n;且 m−n 取所有可能值中的最小值。
輸入格式:
輸入在第 1 行中給出一個正整數 N,第 2 行給出 N 個待填充的正整數。所有數字不超過 10^4,相鄰數字以空格分隔。
輸出格式:
輸出螺旋矩陣。每行 n 個數字,共 m 行。相鄰數字以 1 個空格分隔,行末不得有多餘空格。
輸入樣例:
12
37 76 20 98 76 42 53 95 60 81 58 93
輸出樣例:
98 95 93
42 37 81
53 20 76
58 60 76
具體實現:
package com.hbut.pat;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.Arrays;
public class Pat_1050 {
public static void main(String[] args) throws Exception {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
int length = Integer.parseInt(br.readLine());
int m = 0,n = 0;
int min = 100001;
for (int i = 1; i <= Math.sqrt(length); i++) {
if (length % i == 0) {
int j = length / i;
if (min > j - i) {
m = j;
n = i;
min = m - n;
}
}
}
String[] in = br.readLine().split(" ");
int[] d = new int[length];
for (int i = 0; i < length; i++) {
d[i] = Integer.parseInt(in[i]);
}
Arrays.sort(d);
int[][] data = new int[m][n];
data[0][0] = d[length - 1];
int i = 0, j = 0;
for (int l = length - 2; l >= 0; l--) {
boolean up = false, down = false, left = false, right = false;
if (i - 1 >= 0 && data[i - 1][j] == 0)
up = true;
if (i + 1 < m && data[i + 1][j] == 0)
down = true;
if (j + 1 < n && data[i][j + 1] == 0)
right = true;
if (j - 1 >= 0 && data[i][j - 1] == 0)
left = true;
if (!up && down && !left && right) {
j = j + 1;
data[i][j] = d[l];
continue;
}
if (!up && down && !left && !right) {
i = i + 1;
data[i][j] = d[l];
continue;
}
if (!up && down && left && !right) {
i = i + 1;
data[i][j] = d[l];
continue;
}
if (!up && !down && left && !right) {
j = j - 1;
data[i][j] = d[l];
continue;
}
if (up && !down && left && !right) {
j = j - 1;
data[i][j] = d[l];
continue;
}
if (up && !down && !left && !right) {
i = i - 1;
data[i][j] = d[l];
continue;
}
if (up && !down && !left && right) {
i = i - 1;
data[i][j] = d[l];
continue;
}
if (!up && !down && !left && right) {
j = j + 1;
data[i][j] = d[l];
continue;
}
}
for (i = 0; i < m; i++) {
for (j = 0; j < n - 1; j++) {
System.out.print(data[i][j] + " ");
}
System.out.println(data[i][n - 1]);
}
}
}