第十四届省赛 c++ B组填空题

import java.util.*;

public class Main {

    static int[] a = {5,6,8,6,9,1,6,1,2,4,9,1,9,8,2,3,6,4,7,7,5,9,5,0,3,8,7,5,8,1,5,8,6,1,8,3,0,3,7,9,2,7,0,5,8,8,5,7,0,9,9,1,9,4,4,6,8,6,3,3,8,5,1,6,3,4,6,7,0,7,8,2,7,6,8,9,5,6,5,6,1,4,0,1,0,0,9,4,8,0,9,1,2,8,5,0,2,5,3,3};
    static Set<String> dates = new HashSet<>();
    static int[] daysInMonth = {0,31,28,31,30,31,30,31,31,30,31,30,31};
    static boolean[] used = new boolean[a.length];

    static boolean isValidDate(String dateStr) {
        int year = Integer.parseInt(dateStr.substring(0, 4));
        int month = Integer.parseInt(dateStr.substring(4, 6));
        int day = Integer.parseInt(dateStr.substring(6, 8));

        if (year != 2023 || month < 1 || month > 12 || day < 1 || day > daysInMonth[month]) {
            return false;
        }

        return true;
    }

    static void generateDateSequences(int index, String currentSequence) {
        if (currentSequence.length() == 8) {
            if (isValidDate(currentSequence)) {
                dates.add(currentSequence);
            }
            return;
        }

        // 剪枝：如果当前序列已经无法凑成一个合法日期，则不继续向后递归
        if (currentSequence.length() >= 4) {
            String yearPart = currentSequence.substring(0, 4);
            int year = Integer.parseInt(yearPart);
            if (year != 2023) {
                return;
            }
        }

        // 剪枝：如果当前月份已经大于12，则不继续向后递归
        if (currentSequence.length() >= 6) {
            String monthPart = currentSequence.substring(4, 6);
            int month = Integer.parseInt(monthPart);
            if (month > 12) {
                return;
            }
        }

        // 剪枝：如果当前日期大于当前月份的天数，则不继续向后递归
        if (currentSequence.length() >= 8) {
            String dayPart = currentSequence.substring(6, 8);
            int day = Integer.parseInt(dayPart);
            String monthPart = currentSequence.substring(4, 6);
            int month = Integer.parseInt(monthPart);
            if (day > daysInMonth[month]) {
                return;
            }
        }

        for (int i = index; i < a.length; i++) {
            if (!used[i]) {
                used[i] = true;
                generateDateSequences(i + 1, currentSequence + a[i]);
                used[i] = false;
            }
        }
    }

    public static void main(String[] args) {
        generateDateSequences(0, "");
        System.out.println(dates.size());
    }
}

public class Main {

    public static void main(String[] args) {
        int n = 23333333;
        for (int i = 0; i <= n; i++) {
            double x = (-1.0) * i / n * log2(1.0 * i / n, 2) * i;
            double y = (-1.0) * (n - i) / n * log2(1.0 * (n - i) / n, 2) * (n - i);
            if (x + y >= 11625907.5798) {
                System.out.println(i);
                return;
            }
        }
    }

    //如何计算logx(y)=ln(y)/ln(x);    Math.log(x) = In(x)
    public static double log2(double x, double base) {
        return Math.log(x) / Math.log(base);
    }
}

第十四届省赛 c++ C组填空题

        long res = 0;

        for (int i = 1; i <= 20230408; i++) {
              res += i;
        }

        System.out.println(res);

        /*
          从文档当中把每个数据复制进来
        */
        int res = 0;
        LocalTime startTime = LocalTime.of(12,00,15);
        LocalTime endTime= LocalTime.of(17,16,07);

        while(!startTime.isAfter(endTime)){
            startTime = startTime.plusSeconds(1);
            res++;
        }
        System.out.println(res);

第十四届省赛 java B组填空题

/*
   这题不能用暴力解决，毕竟10的11次方了。
   这题只要求观察出1！到39之和后面的末尾9位数没有变过即可解决.
   如果有接触过这种类型题，可快速完成.
 */
public class Main{
    public static void main(String[] args) {
        long sum=0;
        long t=1000000000;
        long temp=1;
        for(int i=1;i<=10000;i++){
            temp=(temp*i)%t;
            sum=(sum+temp)%t;
            System.out.println(sum);
        }

    }
}

public class Main{

    static boolean check(int x){
        int k = x;
        int sum = 0;
        while(k > 0){
            int t = k % 10;
            sum += t;
            k /= 10;
        }
        if(x % sum != 0){
            return false;
        }

        return true;
    }

    static boolean check2(int x){
        int k = x;
        int sum = 0;
        while(k > 0){
            sum += k % 8;
            k = k / 8;
        }

        if(x % sum != 0){
            return false;
        }

        return true;
    }

    static boolean check3(int x){
        int k = x;
        int sum = 0;
        while(k > 0){
            sum += k % 16;
            k = k / 16;
        }

        if(x % sum != 0){
            return false;
        }

        return true;
    }

    static boolean check4(int x){
        int k = x;
        int sum = 0;
        while(k > 0){
            sum += k % 2;
            k = k / 2;
        }

        if(x % sum != 0){
            return false;
        }

        return true;
    }

    public static void main(String[] args) {
        int res = 0;
        for(int i = 1;;i++){
            if(check(i) && check2(i) && check3(i) && check4(i)){
                //System.out.print(i + " ");
                res++;
            }
            if(res == 2023){
                System.out.println(i);
                return;
            }
        }
    }
}

第十四届省赛 java C组填空题

public class Main {
    public static void main(String[] args) {
        dfs(1, 9, 16);
        System.out.println(sum);
    }

    static int sum = 0;

    static void dfs(int x, int a, int b) {
        if (x == 8) {
            if (a == 0 && b == 0) {
                //如果七个人恰好分完则计数加一
                sum++;
            }
            return;
        }

        for (int i = 0; i <= a; i++) {
            for (int j = 0; j <= b; j++) {
                if (i + j >= 2 && i + j <= 5) {
                    //只有满足2-5的条件才可以
                    dfs(x + 1, a - i, b - j);
                }
            }
        }
    }
}