百练1019:Number Sequence

题目：

描述

A single positive integer i is given. Write a program to find the digit located in the position i in the sequence of number groups S1S2...Sk. Each group Sk consists of a sequence of positive integer numbers ranging from 1 to k, written one after another.
For example, the first 80 digits of the sequence are as follows:
11212312341234512345612345671234567812345678912345678910123456789101112345678910

输入

The first line of the input file contains a single integer t (1 ≤ t ≤ 10), the number of test cases, followed by one line for each test case. The line for a test case contains the single integer i (1 ≤ i ≤ 2147483647)

输出

There should be one output line per test case containing the digit located in the position i.

样例输入

  

   

    

     

    
    

     

      2
     
    
   

    

     

    
    

     

      8
     
    
   

    

     

    
    

     

      3
     
    
  
 

样例输出

  

   

    

     

    
    

     

      2
     
    
   

    

     

    
    

     

      2
     
    
  
 

代码：

  

   

    

     

    
    

     

      n=int(input())
     
    
   

    

     

    
    

     

      def sum(i):#从1到i一共多少个数字
     
    
   

    

     

    
    

     

          if(i<10):
     
    
   

    

     

    
    

     

              return i
     
    
   

    

     

    
    

     

          if(i<100):
     
    
   

    

     

    
    

     

              return i*2-9
     
    
   

    

     

    
    

     

          if(i<1000):
     
    
   

    

     

    
    

     

              return (i-99)*3+sum(99)
     
    
   

    

     

    
    

     

          if(i<10000):
     
    
   

    

     

    
    

     

              return (i-999)*4+sum(999)
     
    
   

    

     

    
    

     

          return (i-9999)*5+sum(9999)
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      while n:
     
    
   

    

     

    
    

     

          n=n-1
     
    
   

    

     

    
    

     

          k=int(input())
     
    
   

    

     

    
    

     

          i=1
     
    
   

    

     

    
    

     

          while sum(i)<k: 
     
    
   

    

     

    
    

     
        i=i+1
     
    
   

    

     

    
    

     
        k=k-sum(i-1)
     
    
   

    

     

    
    

     
    i=1
     
    
   

    

     

    
    

     
    while sum(i)<k:
     
    
   

    

     

    
    

     
        i=i+1
     
    
   

    

     

    
    

     
    k=k-sum(i-1)
     
    
   

    

     

    
    

     

          #i的第k位
     
    
   

    

     

    
    

     
    print(str(i)[k-1])
     
    
  
 

这个代码十分有意思，第-10行到第-7行 和 第-6行到第-3行 只有缩进不一样

文章来源: blog.csdn.net，作者：csuzhucong，版权归原作者所有，如需转载，请联系作者。

原文链接：blog.csdn.net/nameofcsdn/article/details/75201323