NOIP 模拟赛总结
NOIP 模拟赛 9
调了一整场的 T2，样例全过！只有 40 pts。QxQ
T1 卡门
连续两场 T1 放数据结构了欸
数据结构题，直接分块就行。
赛时没算时间复杂度，导致打了个暴力交上去以为是正解。
赛后半小时改完，挂挂挂！
点击查看代码
#include <stdio.h>
#include <vector>
#include <iostream>
#include <string.h>
#include <algorithm>
#include <cmath>
#define con putchar_unlocked(' ')
#define ent putchar_unlocked('\n')
#define Blue_Archive return 0
using namespace std;
constexpr int N = 3e4 + 3;
constexpr int B = 175;
constexpr int M = 31;
constexpr int me = 0x0d000721;int n;
int m;
int K;
int ans;
int len;
int L[B];
int R[B];
int id[N];pair<int,int> to[B][M];int mp[N][M];inline void dfs_init(int x,int y,int dep,pair<int,int>&op)
{if(x == dep) return void(op = {x,y});if(!mp[x + 1][y]) dfs_init(x + 1,y,dep,op);else if(mp[x + 1][y] == 2){if(y > 1 && !mp[x][y - 1] && !mp[x + 1][y - 1]) dfs_init(x,y - 1,dep,op);else if(y < m && !mp[x][y + 1] && !mp[x + 1][y + 1]) dfs_init(x,y + 1,dep,op);else return void(op = {x,y});}else return void(op = {x,y});
}inline void init()
{int len = sqrt(n);for(int i = 1;i <= n;i ++){id[i] = (i - 1) / len + 1;if(!L[id[i]]) L[id[i]] = i;R[id[i]] = i;}for(int i = 1;i < id[n];i ++){for(int j = 1;j <= m;j ++){dfs_init(L[i],j,R[i] + 1,to[i][j]);}}for(int i = 1;i <= m;i ++) dfs_init(L[id[n]],i,n,to[id[n]][i]);
}inline void query(int x)
{int now = x;int op = 0;for(int i = 1;i <= id[n];i ++){if(to[i][now].first != R[i] + 1) break;op = i;now = to[i][now].second;}op ++;mp[to[op][now].first][to[op][now].second] = 2;if(to[op][now].first == L[op]){for(int i = 1;i <= m;i ++){if(to[op - 1][i].first == L[op] && to[op - 1][i].second == to[op][now].second) dfs_init(L[op - 1],i,R[op - 1] + 1,to[op - 1][i]);}}for(int i = 1;i <= m;i ++){dfs_init(L[op],i,min(R[op] + 1,n),to[op][i]);}
}signed main()
{freopen("kamen.in","r",stdin);freopen("kamen.out","w",stdout);// freopen("data.in","r",stdin);freopen("data.out","w",stdout);ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);cin >> n >> m;char op;for(int i = 1;i <= n;i ++){for(int j = 1;j <= m;j ++){cin >> op;mp[i][j] = (op == '.') ? 0 : 1;}}init();cin >> K;for(int i = 1,x;i <= K;i ++){cin >> x;query(x);}for(int i = 1;i <= n;i ++){for(int j = 1;j <= m;j ++){if(mp[i][j] == 0) cout << '.';else if(mp[i][j] == 1) cout << 'X';else if(mp[i][j] == 2) cout << 'O';}cout << '\n';}Blue_Archive;
}
T2 商人
5 个样例全过，只得 40 pts，qwq。
考虑建反图
点击查看代码
#include <stdio.h>
#include <vector>
#include <iostream>
#include <string.h>
#include <algorithm>
#include <bitset>
#include <queue>
#define int long long
#define add(u,v) to[++ tot] = v,nxt[tot] = h[u],h[u] = tot
#define con putchar_unlocked(' ')
#define ent putchar_unlocked('\n')
#define Blue_Archive return 0
using namespace std;
constexpr int N = 2e5 + 3;
constexpr int me = 0x0d00721;
constexpr int INF = 1e9;int n;
int m;
int tot;
int h[N];
int in[N];
int to[N];
int nxt[N];
int ans[N];bitset<N> vis;queue<int> q;struct miku
{int x,y,r,p;friend bool operator < (miku a,miku b){return a.r < b.r;}
}eg[N];signed main()
{freopen("merchant.in","r",stdin);freopen("merchant.out","w",stdout);// freopen("data.in","r",stdin);freopen("data.out","w",stdout);ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);cin >> n >> m;for(int i = 1,x,y,r,p;i <= m;i ++){cin >> x >> y >> r >> p;eg[i] = {x,y,r,p};in[x] ++;}memset(ans,0x3f,sizeof(ans));sort(eg + 1,eg + m + 1);for(int i = 1;i <= m;i ++) add(eg[i].y,i);for(int i = 1;i <= n;i ++) if(!in[i]) q.push(i);for(int i = m;i >= 1;i --){while(!q.empty()){int u = q.front();q.pop();for(int j = h[u];j;j = nxt[j]){if(vis[to[j]]) continue;vis[to[j]] = 1;-- in[eg[to[j]].x];if(!in[eg[to[j]].x]) q.push(eg[to[j]].x);if(ans[u] < INF) ans[eg[to[j]].x] = min(ans[eg[to[j]].x],max(eg[to[j]].r,ans[u] - eg[to[j]].p));}}if(!vis[i]){vis[i] = 1;-- in[eg[i].x];if(!in[eg[i].x]) q.push(eg[i].x);ans[eg[i].x] = min(ans[eg[i].x],eg[i].r);}}for(int i = 1;i <= n;i ++) cout << ((ans[i] > INF) ? -1 : ans[i]) << ' ';Blue_Archive;
}
T3：自行车
不会，咕咕。
T4： 记忆
不会，咕咕。