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(python)百練1019:Number Sequence

題目:

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 輸入 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) 輸出 There should be one output line per test case containing the digit located in the position i. 樣例輸入
2
8
3
樣例輸出
2
2

程式碼:

n=int(input())
def sum(i):#從1到i一共多少個數字
    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])

這個程式碼十分有意思,第-10行到第-7行 和 第-6行到第-3行 只有縮排不一樣