zoukankan      html  css  js  c++  java
  • 2C Numerical Sequence (hard version)

    题目

    The only difference between the easy and the hard versions is the maximum value of k.

    You are given an infinite sequence of form "112123123412345…" which consist of blocks of all consecutive positive integers written one after another. The first block consists of all numbers from 1 to 1, the second one — from 1 to 2, the third one — from 1 to 3, …, the i-th block consists of all numbers from 1 to i.

    So the first 56 elements of the sequence are "11212312341234512345612345671234567812345678912345678910". Elements of the sequence are numbered from one. For example, the 1-st element of the sequence is 1, the 3-rd element of the sequence is 2, the 20-th element of the sequence is 5, the 38-th element is 2, the 56-th element of the sequence is 0.

    Your task is to answer q independent queries. In the i-th query you are given one integer (k_i). Calculate the digit at the position (k_i) of the sequence.

    Input

    The first line of the input contains one integer (q (1≤q≤500)) — the number of queries.

    The i-th of the following q lines contains one integer (k_i (1≤k_i≤10^{18})) — the description of the corresponding query.

    Output

    Print q lines. In the i-th line print one digit (x_i (0≤x_i≤9)) — the answer to the query (i, i.e. x_i) should be equal to the element at the position (k_i) of the sequence.

    Examples

    Input 1

    5
    1
    3
    20
    38
    56
    

    Output 1

    1
    2
    5
    2
    0
    

    Input 2

    4
    2132
    506
    999999999999999999
    1000000000000000000
    

    Output 2

    8
    2
    4
    1
    

    Note

    Answers on queries from the first example are described in the problem statement.

    题解

    解题思路

    这道题数据很大,1e18,常规做法数组是开不下的
    我们就按位数来存

    (a_i)表示有i位数的数字的总长度:1-9, 10-99;
    (b_i)(a_i)的前缀和:1-9, 1-99;
    (c_i)是到了第i个时数列的长度,

    (c_1) 1-1 + 1-2 + ... + 1-9;
    (c_2) 1-1 + 1-2 + ... + 1-99;

    代码

    #include <cstdio>
    #include <algorithm>
    #define int long long
    using namespace std;
    int t, k, a[20], b[20], c[20];
    signed main() {
        for(int i = 1; i <= 10; i++) {
            int x = i, l = 1, r = 9;
            while (--x) l *= 10, r = r * 10 + 9;
            a[i] = (r - l + 1) * i;
            b[i] = b[i-1] + a[i];
            c[i] = c[i-1] + (b[i-1] + i + b[i]) * (r - l + 1) / 2;
        }//预处理
        scanf("%lld", &t);
        while (t--) {
            scanf("%lld", &k);
            int d = lower_bound(c+1, c+11, k) - c;
            k -= c[d-1];
            int l = 1, r = 9, x = d;
            while (--x) l *= 10, r = r * 10 + 9;
            int L = l;
            while (l <= r) {
                int mid = (l + r) >> 1;
                if ((2 * b[d-1] +d + (mid - L + 1) * d) * (mid - L + 1) / 2 >= k) r = mid - 1;
                else l = mid + 1;
            }
            k -= (2 * b[d-1] + d + (l - L) * d) * (l - L) / 2;
            d = lower_bound(b+1, b+11, k) - b;
            k -= b[d-1];
            int ans = 1, num;
            for(int i = 1; i < d; i++) ans *= 10;
            num = (k - 1) / d;
            k -= num * d;
            ans += num;
            k = d - k;
            while (k--) ans /= 10;
            printf("%lld
    ", ans % 10);
        }
        return 0;
    }
    
  • 相关阅读:
    能打开电脑都看懂的系列之Windows下修改MongoDB用户密码
    vue element el-input 输入框当内容长度超出时显示el-tooltip提示
    vue 数据代理帮助类 ux-data-proxy
    微信小程序全局设置分享内容
    解决vscode更新后Ext Js插件无法使用问题
    ux.form.field.Year 只能选年的时间扩展
    ux.form.field.Month 只能选年、月的时间扩展
    Ext Js 6+ 动态切换皮肤
    Ext Js 6.2.1 classic grid 滚动条bug解决方案
    Ext-JS-Modern-Demo 面向移动端示例
  • 原文地址:https://www.cnblogs.com/shawk/p/12792925.html
Copyright © 2011-2022 走看看