2025/03/07训练

2025/03/07训练

1、L2-006 树的遍历

n = int(input())
a1 = list(map(int,input().split()))
a2 = list(map(int,input().split()))

def solve(a_start,a_end,b_start,b_end):
    if a_start > a_end:
        return None
    newtree = [a1[a_end],-1,-1]
    root_index = b_start
    #找根节点
    while a2[root_index] != newtree[0]:
        root_index += 1
    left_length = root_index - b_start
    newtree[1] = solve(a_start,a_start+left_length-1,b_start,root_index-1)
    newtree[2] = solve(a_start+left_length,a_end-1,root_index+1,b_end)
    return newtree
tree = solve(0,n-1,0,n-1)
#print(tree)
if tree:
    res = []
    queue = [tree]
    while queue:
        print(queue)
        now_nodes = []
        next_level = []
        for x in queue:
            now_nodes.append(x[0])
            if x[1]:
                next_level.append(x[1])
            if x[2]:
                next_level.append(x[2])
        res.append(now_nodes)
        queue = next_level
cnt = 0
print(tree)
print(res)
for x in res:
    for y in x:
        if cnt:
            print(" ",end ='')
        else :
            cnt = 1
        print(y,end = '')

2、L1-058 6翻了

num = input()
num += '?'
ans = 0
answer = ''
for i in num:
    if i == '6':
        ans += 1
    else :
        if i == '?':
            i = ''
        if ans > 9:
            answer += '27'+i
        elif ans > 3:
            answer += '9'+i
        else :
            answer += '6'*ans+i
        ans = 0
print(answer)

3、L2-008 最长对称子串

#include<bits/stdc++.h> 
using namespace std;
const int MAX=110000+10;  
char s[MAX*2];  
int p[MAX*2]; 
int manachar()
{
	memset(p,0,sizeof(p));
    int len = strlen(s);
    int id = 0;
    int maxlen = 0;
    for(int i = len;i >= 0;i--){
        s[i+i+2] = s[i];
        s[i+i+1] = '#';
    }
    s[0] = '*';
	for(int i = 2;i < 2*len + 1;i++){
        if(p[id] + id > i){
            p[i] = p[2*id - i] < p[id]+id-i ? p[2*id - i] : p[id]+id-i;
        }else{
            p[i] = 1;
        }
        while(s[i - p[i]] == s[i + p[i]]){
            p[i]++;
        }
        if(id + p[id] < i + p[i]){
            id = i;
        }
        if(maxlen < p[i]){
            maxlen = p[i];
        }
    }
    return maxlen-1;
}
int main() 
{
	std::ios::sync_with_stdio(false);
	string ss;
	getline(cin,ss);
	for(int i=0;i<ss.length();i++)
	{
		s[i] = ss[i];
	}
    int ans = manachar();
    cout << ans << endl;
    return 0;
}