165. Compare Version Numbers

今天项目里遇到以"." 、""、“|”分割字符串，直接用"." 、""、“|”无法分割，因为"." 、""、“|”是特殊字符，需要转义，"." 、""、“|”。

class Solution {
	  public int compareVersion(String version1, String version2) {
	      String[] arr1 = version1.split("\.");
	      String[] arr2 = version2.split("\.");
	      int n = arr1.length>arr2.length?arr1.length:arr2.length;
	      int temp1[] = new int [n];
	      int temp2[] = new int [n];
	      for(int i = 0 ; i < arr1.length ; i++) {
	    	  temp1[i] = Integer.parseInt(arr1[i]);
	      }
	      for(int i = 0 ; i < arr2.length ; i++) {
	    	  temp2[i] = Integer.parseInt(arr2[i]);
	      }
	      int flag = 0;
	      while(flag<n) {
	    	  if(temp1[flag]<temp2[flag])
	    		  return -1;
	    	  else if(temp1[flag]>temp2[flag])
	    		  return 1;
	    	  flag++;
	      }
		  return 0;
	    }
	  }

精简~

class Solution {
   public int compareVersion(String s1, String s2) {
		  int i = 0 ; 
		  int j = 0 ; 
		  while( i < s1.length() || j < s2.length()) {
			  int x = i ;
			  int y = j ;
			  while(x<s1.length()&&s1.charAt(x)!='.')x++;
			  while(y<s2.length()&&s2.charAt(y)!='.')y++;
			  int a = i==x?0:Integer.valueOf(s1.substring(i, x));
			  int b = j==y?0:Integer.valueOf(s2.substring(j, y));
			  if(a>b)return 1;
			  else if(a<b)return -1;
			  i = x+1;
			  j = y+1;
		  }
		  return 0;
	    }
	  }