Java(javac 1.8) 解法, 执行用时: 26ms, 内存消耗: 12008K, 提交时间: 2021-04-20 14:39:01

import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        char[] abs = s.toCharArray();
        long high = 0,c = 1;
        for(int i=0;i<abs.length;i++){
            if(i>=1) {
                if (abs[i]==abs[i - 1])
                    c *= 2;
                else
                    c = 1;
            }
            if(abs[i]=='u')
                high += c;
            else
                high -= c;
        }

        System.out.println(high);
    }
}

C 解法, 执行用时: 2ms, 内存消耗: 392K, 提交时间: 2021-05-28 16:56:47

#include<stdio.h>
#include<stdlib.h>
int main(){
	char a[64];
	gets(a);
	long x=1;
	long sum=0;
	if(a[0]=='u') sum=1;
	if(a[0]=='d') sum=-1; 
	for(int i=1;i<64;i++){
		if(a[i]=='u'&&a[i-1]=='u'){
			x=x*2;
			sum=sum+x;
		}
	    if(a[i]=='u'&&a[i-1]=='d'){
			x=1;
			sum=sum+x;
		}
		if(a[i]=='d'&&a[i-1]=='d'){
		    x=x*2;
		    sum=sum-x; 
	    }
	    if(a[i]=='d'&&a[i-1]=='u'){
	    	x=1;
	    	sum=sum-x;
		}
 }
 printf("%lld",sum);
}

Python3(3.9) 解法, 执行用时: 17ms, 内存消耗: 2816K, 提交时间: 2021-05-11 19:15:14

n = input()
s = 0
s1 = 1
if n[0] == "u":
    s += 1
else:
    s -= 1
for i in range(1,len(n)):
    if n[i] == n[i-1] == "u":
        s1 *= 2
        s += s1
    elif n[i] == n[i-1] =="d":
        s1 *= 2
        s -= s1
    if n[i] != n[i-1]:
        s1 = 1
        if n[i] == "u":
            s += 1
        else:
            s -= 1
print(s)
        

C++(clang++11) 解法, 执行用时: 11ms, 内存消耗: 412K, 提交时间: 2021-04-23 12:43:03

#include<iostream>
#include<algorithm>
#include<cstring>
using namespace std;
int main()
{
	string s;
	cin>>s;
	long long int h=1,sum=0;
	for(int i=0;i<s.size();i++)
	{
		if(i==0||s[i]!=s[i-1])
		h=1;
		else if(s[i]==s[i-1])
		h*=2;
		if(s[i]=='u')
		{
			sum+=h;
		}
		else if(s[i]=='d')
		{
			sum-=h;
		}
	}
	printf("%lld",sum);
	return 0;
}