京东JAVA笔试两题

刺骨的言语ヽ痛彻心扉 2021-09-18 02:40 346阅读 0赞

![5057999-2a4ed2e7a571a56f.png][]

网络上找的图片

通过队列实现 queue.size获得对应的总数大小 进行相应的入队出队操作

public class Main{
    
        public static void main(String[] args) {
            // TODO Auto-generated method stub
                Scanner sc=new Scanner(System.in);
                while(sc.hasNext()){
                    String s=sc.nextLine();
                    function(s);
                }
        }
    
        private static void function(String s){
            Queue queue=new LinkedList<>();
            int count=1;
            char[] chars=s.toCharArray();
            queue.add(chars[0]);
            for(int i=1;i<chars.length;i++){
                if(chars[i]=='(')
                    queue.add(chars[i]);
                else{
                    count=count*queue.size();
                    queue.poll();
                }
            }
            System.out.println(count);
        }
    }

![5057999-3154032216765367.png][]

public class Main{
    
    
        public final static long MOD=1000000000+7;
        
        public static long gcd(long a,long b){//最大公约数
            return (a%b==0)?b:gcd(b,a%b);
        }
        
        public static void main(String[] args) {
            // TODO Auto-generated method stub
            Scanner sc=new Scanner(System.in);
            while(sc.hasNext()){
                long n=sc.nextLong();
                long ans=(long)1*n*(n*2-1)%MOD;
                Set<Integer> set=new HashSet<>();
                for(int i=2;i*i<=n;i++){
                    if(set.contains(i))
                        continue;
                    long tmp=i;
                    int cnt=0;
                    while(tmp<=n){
                        set.add((int)tmp);
                        tmp=tmp*i;
                        cnt++;
                    }
                    for(int k=1;k<=cnt;k++){
                        for(int j=k+1;j<=cnt;j++)
                            ans=(ans+n/(j/gcd(k,j))*(long)2)%MOD;
                    }
                }
                System.out.println(ans);
            }
        }
    }

[5057999-2a4ed2e7a571a56f.png]: /images/20210811/779b7ef32a374d35b6356c67283d1d27.png
[5057999-3154032216765367.png]: /images/20210811/c9c152145ea64512911fe4de81de2815.png