哆啦A梦的时光机

#include<iostream>
#include<cstring>
#include<algorithm>
#include<queue>

using namespace std;

struct node 
{
    int value;
    int dis;
};

const int N = 1e6 + 10;
bool vis[N];


int bfs(int st, int ed, int dis) 
{
    memset(vis, 0, sizeof vis);
    queue<node> q;
    node One, next;
    One.value = st;
    One.dis = dis;
    q.push(One);
    vis[st] = true;

    while (!q.empty()) 
    {
        node t = q.front();
        q.pop(); 
        if (t.value == ed) 
            return t.dis * 2;
        next.value = t.value + 1;
        if (next.value && next.value < 1000000 && !vis[next.value]) 
        {
            next.dis = t.dis + 1;
            q.push(next);
            vis[next.value] = true;
        }
        next.value = t.value - 1;
        if (next.value && next.value < 1000000 && !vis[next.value]) 
        {
            next.dis = t.dis + 1;
            q.push(next);
            vis[next.value] = true;
        }     
        next.value = t.value * 2;
        if (next.value && next.value < 1000000 && !vis[next.value]) 
        {
            next.dis = t.dis + 1;
            q.push(next);
            vis[next.value] = true;
        }       
        if (t.value % 2 == 0) 
        {
            next.value = t.value / 2;
            if (next.value && next.value < 1000000 && !vis[next.value]) {
                next.dis = t.dis + 1;
                q.push(next);
                vis[next.value] = true;
            }
        }
    }
}

int main() {
    int T;
    cin >> T;

    while (T -- )
    {
        int s, t;
        cin >> s >> t;
        cout << bfs(s, t, 0) << endl;
    }

    return 0;
}

最小新整数

#include<iostream>
#include<cstring>
#include<algorithm>
#include<cmath>
#include <string>
using namespace std;

string str;
bool st[20];
int k, res;

void dfs(int step){
    if (step == k){
        int ans = 0;
        int pos = 0;
        for (int i = 0; i < str.size(); i ++ ){
            if (!st[i]){
                ans += (str[i] - '0') * pow(10, str.size() - k - 1 - pos);
                pos ++ ;
            }
        }
        res = min(res, ans);
        return;
    }
    for (int i = 0; i < str.size(); i ++ ){
        if (!st[i]){
            st[i] = true;
            dfs(step + 1);
            st[i] = false;
        }
    }
}

int main() {
    int T;
    cin >> T;

    while (T -- ){
        memset(st, false, sizeof st);
        cin >> str >> k;
        res = 1e9;
        dfs(0);
        cout << res << endl;
    }

    return 0;
}

上白泽慧音

#include <iostream>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <string>
#include <queue>
using namespace std;
const int N = 5010, M = 1e5 + 10;

struct Node{
    int p, size = 0;
    int dic;
} p[N];
priority_queue<int, vector<int>, greater<int>> ans[N];
int n, m;
int h[N], e[M], ne[M], idx;
int belong[N], bent, stk[N], top, dfn[N], low[N], instk[N], timestamp;

bool cmp(Node A, Node B){
    if (A.size != B.size) return A.size > B.size;
    else return A.dic < B.dic;
}

void add(int a, int b){
    e[idx] = b, ne[idx] = h[a], h[a] = idx ++ ;
}

void tarjan(int u){
    dfn[u] = low[u] = ++ timestamp;
    stk[++ top] = u, instk[u] = true;
    for (int i = h[u]; ~i; i = ne[i]){
        int j = e[i];
        if (!dfn[j]){
            tarjan(j);
            low[u] = min(low[u], low[j]);
        }else if (instk[j]) low[u] = min(low[u], dfn[j]);
    }
    if (dfn[u] == low[u]){
        int v;
        ++ bent;
        p[bent].dic = stk[top];
        do{
            v = stk[top --];
            instk[v] = false;
            belong[v] = bent;
            p[bent].p = bent;
            p[bent].size ++ ;
            ans[bent].push(v);
        }while(v != u);
    }
}

int main() {
    memset(h, -1, sizeof h);
    cin >> n >> m;
    while (m -- ){
        int a, b, c;
        cin >> a >> b >> c;
        add(a, b);
        if (c == 2) add(b, a);
    }
    for (int i = 1; i <= n; i ++ )
        if (!dfn[i])
            tarjan(i);
    sort(p + 1, p + 1 + bent, cmp);
    cout << p[1].size << endl;
    while (!ans[p[1].p].empty()){
        cout << ans[p[1].p].top() << ' ';
        ans[p[1].p].pop();
    }
    return 0;
}