腾讯开发岗笔试题解Java

第一题：就是一个找规律

public class Q1 {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long n = sc.nextInt();
        long m = sc.nextInt();
        long count = m * m;
        long sum = n / (2 * m) * count;
        System.out.println(sum);
    }
}

第二题：dp

public class Q2 {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int K = sc.nextInt();
        int A = sc.nextInt();
        int X = sc.nextInt();
        int B = sc.nextInt();
        int Y = sc.nextInt();

        int[][] dp = new int[X+Y+1][K+1];

        for (int i = 0; i < X+Y+1; i++)
            dp[i][0] = 1;

        for (int i = 1; i < X+Y+1; i++) {
            for (int j = 1; j <= K; j++) {
                if (i <= X) {
                    if (j >= A) dp[i][j] = (dp[i-1][j] + dp[i-1][j-A]) % 1000000007;
                    else dp[i][j] = dp[i-1][j] % 1000000007;
                }
                else if (i <= X+Y) {
                    if (j >= B) dp[i][j] = (dp[i-1][j] + dp[i-1][j-B]) % 1000000007;
                    else dp[i][j] = dp[i-1][j] % 1000000007;
                }
            }
        }

        System.out.println(dp[X+Y][K]);

    }
}

第三题：贪心，排序求和

public class Q3 {

    static class Pair {
        int time;
        int level;

        public Pair(int time, int level) {
            this.time = time;
            this.level = level;
        }
    }


    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int m = sc.nextInt();

        Pair[] machine = new Pair[n];
        Pair[] task = new Pair[m];

        // input
        for (int i = 0; i < n; i++)
            machine[i] = new Pair(sc.nextInt(), sc.nextInt());
        for (int i = 0; i < m; i++)
            task[i] = new Pair(sc.nextInt(), sc.nextInt());
        int[] cnt = new int[105];

        // sort
        Comparator<Pair> comparator = (a, b) -> {
            if (a.time == b.time)   return b.level - a.level;
            else return b.time - a.time;
        };
        Arrays.sort(machine, comparator);
        Arrays.sort(task, comparator);

        long sum = 0;

        int j = 0, cnt1 = 0;
        for(int i = 0;i < m;i++) {
            while(j < n && machine[j].time >= task[i].time) {
                  cnt[machine[j].level]++;
                  j++;
            }
            for(int k = task[i].level; k < 101; k++) {
                if(cnt[k] != 0) {
                    cnt[k]--;
                    sum += 200*task[i].time + 3*task[i].level;
                    cnt1++;
                    break;
                }
            }
        }
        System.out.println(cnt1 + " " + sum);
    }
}