image.png

思路

  • 直接找到.的位置，将切割出前面的字符串，将其转换为数字再进行比较

    代码

    1.   public int compareVersion(String version1, String version2) {
    2.       return recur(version1, 0, version2, 0);
    3.   }
    5.   public int recur(String version1, int startI, String version2, int startJ) {
    6.       if (startI >= version1.length() && startJ >= version2.length()) return 0;
    7.       int i = 0, j = 0;
    8.       for (i = startI; i < version1.length(); i++) {
    9.           if (version1.charAt(i) == '.') break;
    10.       }
    11.       for (j = startJ; j < version2.length(); j++) {
    12.           if (version2.charAt(j) == '.') break;
    13.       }
    14.       Integer s1 = startI >= version1.length() ? 0 : 
    15.                   Integer.valueOf(version1.substring(startI, i));
    16.       Integer s2 = startJ >= version2.length() ? 0 :
    17.                   Integer.valueOf(version2.substring(startJ, j));
    18.       if (s1 == s2) return recur(version1, i + 1, version2, j + 1);
    19.       return s1 > s2 ? 1 : -1;
    20.   }

    比较版本号