Ultraviolet A-10706 Number Sequence

First find the set in which it is located, then find the element in the Set, and finally find the number of digits of the element.

#include<iostream>#include<algorithm>#include<cstdio>#include<cstring>using namespace std;long long table[100010];long long psum[100010];int n=100000;void maketable(){    int i,flag=1,x=0;    for(i=1;i<=n;i++)    {        if(i%flag==0)        {            flag*=10;            x++;        }        table[i]=table[i-1]+x;        psum[i]+=table[i]+psum[i-1];    }}int main(){    //freopen("in","r",stdin);    //freopen("out","w",stdout);    maketable();    int T,i,t;    long long x;    char s[100];    cin>>T;    while(T--)    {        cin>>x;        i=lower_bound(psum,psum+n,x)-psum;        if(psum[i]==x)            cout<<i%10<<endl;        else        {            x-=psum[i-1];            i=lower_bound(table,table+n,x)-table;            if(table[i]==x)                cout<<i%10<<endl;            else            {                x-=table[i-1];                sprintf(s,"%d",i);                cout<<s[x-1]<<endl;            }        }    }    return 0;}

UV-10706

Number Sequence

Time limit:3000 Ms

Memory limit:Unknown

64bit Io format:% LLD & % LlU

Submitstatus

Description

Problem B
Number Sequence
Input:Standard Input
Output:Standard output
Time limit:1 second

A single positive integerIIs given. Write a program to find the digit located in the positionIIn the sequence of Number GroupsS1s2... SK. Each groupSKConsists of a sequence of positive integer numbers ranging from1ToK, Written one after another. For example, the first80Digits of the sequence are as follows:

11212312341234512345612345671234567812345678912345678910123456789101112345678910

Input

The first line of the input file contains a single integerT (1 <= T <= 25), The number of test cases, followed by one line for each test case. The line for a test case contains the single integerI (1 <= I <= 2147483647)

 

Output

There shoshould be one output line per test case containing the digit located in the positionI.

 

Sample input output for sample input

2 8 3

2 2

Problem Source: Iranian contest

Special thanks: Shahriar Manzoor, EPS.

Source

Root: aoapc I: Beginning algorithm contests (rujia Liu): Volume 4. Algorithm Design
Root: Competitive programming 2: This increases the lower bound of programming contests. Again (Steven & Felix Halim): Problem Solving Paradigms: Divide and conquer-Binary Search

Root: Competitive programming 3: the new lower bound of programming contests (Steven & Felix Halim): Problem Solving Paradigms: Divide and conquer: Binary Search

Ultraviolet A-10706 Number Sequence