一种字符串和数字的对应关系

谁践踏了优雅 2022-05-27 02:51 175阅读 0赞

![20180410134324976][]

//一种字符串和数字的对应关系
    public class StrMatchInt{
    	
        //K伪进制表示法
        public static String getString(char[]chs,int n)
        {
        	  if(chs==null||chs.length==0||n<1)
        	  {
        	  	 return "";
        	  }
        	  int cur=1;
        	  int base=chs.length;
        	  int len=0;
        	  while(n>=cur)
        	  {
        	  	  len++;
        	  	  n-=cur;
        	  	  cur*=base;
        	  }
        	  char[]res=new char[len];
        	  int index=0;
        	  int nCur=0;
        	  do{
        	  	 cur/=base;
        	  	 nCur=n/cur;
        	  	 res[index++]=getKthCharAtChs(chs,nCur+1);
        	  	 n%=cur;
        	  }while(index!=res.length);
        	  return String.valueOf(res);
        }
    
        //获得第k个位置的字符
        public static char getKthCharAtChs(char[]chs,int k)
        {
        	 if(k<1||k>chs.length)
        	 {
        	 	 return 0;
        	 }
        	 return chs[k-1];
        }
        //******************************************************
        //字符串转数字
        public static int getNum(char[]chs,String str)
        {
        	 if(chs==null||chs.length==0)
        	 {
        	 	 return 0;
        	 }
        	 char[]strc=str.toCharArray();
        	 int base=chs.length;
        	 int cur=1;
        	 int res=0;
        	 for(int i=strc.length-1;i!=-1;i--)
        	 {
        	 	  res+=getNthFromChar(chs,strc[i])*cur;
        	 	  cur*=base;
        	 }
        	 return res;
        }
        public static int getNthFromChar(char[]chs,char ch)
        {
        	  int res=-1;
        	  for(int i=0;i!=chs.length;i++)
        	  {
        	  	   if(chs[i]==ch)
        	  	   {
        	  	   	   res=i+1;
        	  	   	   break;
        	  	   }
        	  }
        	  return res;
        }
    	public static void main(String[]args)
    	{
    		 //System.out.println("Hello");
           char[] chs = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K',
    				'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W',
    				'X', 'Y', 'Z' };
    		int len = 1;
    		String res = "";
    		for (int i = 1; i != 705; i++) {
    			res = getString(chs, i);
    			if (res.length() != len) {
    				len = res.length();
    				System.out.println("========================");
    			}
    			System.out.print(res + " ");
    			if (i % chs.length == 0) {
    				System.out.println();
    			}
    		}
    		System.out.println();
    		System.out.println("========================");
    		int testNum = 78128712;
    		System.out.println(getNum(chs, getString(chs, testNum)));
    		String testStr = "BZZA";
    		System.out.println(getString(chs, getNum(chs, testStr)));
    
    
    	}
    }

![1000][]

[20180410134324976]: /images/20220527/d25b87fad35246f4b8819ce9d2b7d8d0.png
[1000]: /images/20220527/6d1acf598cac439688e0c97be1c126af.png