合并连续数字的算法

public class Test { public static void main(String[] args) { String str = new String( "1,2,3,4,5,6,7,8,9,11,13,14,1000,1001,1002,1003"); String[] s = str.split(","); int[] num = new int[s.length]; String result = ""; for (int i = 0; i < s.length; i++) { num[i] = Integer.parseInt(s[i]); } for (int i = 0; i < num.length; i++) { if (i == 0) { result = "" + num[i]; } else if (i == num.length - 1) { if (num[i] - num[i - 1] == 1) { result = result + "-" + num[i]; } else { result = result + "," + num[i]; } } else { if ((num[i] - num[i - 1] == 1) && (num[i + 1] - num[i] == 1)) { continue; } if ((num[i] - num[i - 1] == 1) && (num[i + 1] - num[i] != 1)) { result = result + "-" + num[i]; } if ((num[i] - num[i - 1] != 1)) { result = result + "," + num[i]; } } } System.out.println(result); } }