2018-2019 ACM-ICPC Southeastern European Regional Programming Contest (SEERC 2018)

题目链接:https://vjudge.net/contest/339284#overview

 

A.Numbers

待做

B.Broken Watch




s = input()
s = s.split(" ")
A,B,C,N = list(map(int,s))

n = (N-1) // 2 

ret = N*N*N - 3*N*(n)*(n-1) - N - 3*N*(N-1) 

ans = ret
mod = 1<<64


if (A==B and B==C) :
    ans = ans // 6
elif A==B or B==C or A==C :
    ans = ans //2


print (ans%mod)

C.Tree

枚举根节点然后bfs找最近的m个点

/*************************************************************** 
    > File Name        : a.cpp
    > Author        : Jiaaaaaaaqi
    > Created Time    : 2019年10月31日 星期四 13时30分46秒
 ***************************************************************/

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#define  lowbit(x)  x & (-x)
#define  mes(a, b)  memset(a, b, sizeof a)
#define  fi         first
#define  se         second
#define  pb         push_back
#define  pii        pair

typedef unsigned long long int ull;
typedef long long int ll;
const int    maxn = 1e2 + 10;
const int    maxm = 1e5 + 10;
const ll     mod  = 1e9 + 7;
const ll     INF  = 1e18 + 100;
const int    inf  = 0x3f3f3f3f;
const double pi   = acos(-1.0);
const double eps  = 1e-8;
using namespace std;

int n, m;
int cas, tol, T;

struct Node {
	int u;
	int cnt;
};
int a[maxn];
bool vis[maxn];
int p[maxn];
vector vv[maxn];

int dis[maxn][maxn];

ll solve(int st) {
	mes(vis, 0);
	vis[st] = 1;
	queue q;
	Node now, nex;
	now.u = st, now.cnt = 0;
	q.push(now);
	int cnt = 0;
	while(!q.empty()) {
		now = q.front();
		q.pop();
		if(p[now.u]) {
			a[++cnt] = now.u;
			if(cnt == m)	break;
		}
		for(auto v : vv[now.u]) {
			if(vis[v])	continue;
			vis[v] = 1;
			nex.u = v, nex.cnt = now.cnt+1;
			q.push(nex);
		}
	}
	int ans = 0;
	for (int i=1;i<=cnt;i++) {
		for (int j=i+1;j<=cnt;j++) {
			ans = max(ans,dis[a[i]][a[j]]);
		}
	}
	return ans;
}

void dfs(int u,int fa,int d,int* di){
	di[u] = d;
	for (int v:vv[u]) if (v != fa) {
		dfs(v,u,d+1,di);
	}
}

int main() {
	// freopen("in", "r", stdin);
	scanf("%d%d", &n, &m);
	for(int i=1; i<=n; i++) {
		scanf("%d", &p[i]);
		vv[i].clear();
	}
	for(int i=1, u, v; i

D.Space Station

#include
using namespace std;
const int mx = 1e3+5;
typedef long long ll;
struct edge{
	int v,w;
};
vectorg[mx];
int dp[mx][mx*2];
int sum[mx*2];
int sz[mx];
int n,m,k;
void dfs(int u,int fa){
	sz[u] = 2;
	dp[u][1] = dp[u][0] = 0;
	for(edge it: g[u]){
		int v = it.v;
		int w = it.w;
		if(v==fa)	continue;
		dfs(v,u);
		memset(sum,63,sizeof(sum));
		for(int i = 0; i <= sz[u]; i++)
			for(int j = 0; j <= sz[v]; j++){
				int k = i+j;
				if(j&1) sum[k] = min(sum[k],dp[v][j]+dp[u][i]+w);
				else sum[k] = min(sum[k],dp[v][j]+dp[u][i]+2*w);
			}
		sz[u] += sz[v];
		memcpy(dp[u],sum,sizeof(sum));
	}
}
int main(){
	int t;
	scanf("%d",&t);
	while(t--){ 
		scanf("%d%d%d",&n,&m,&k);
		memset(dp,63,sizeof(dp));
		for(int i = 1; i <= n; i++)
			g[i].clear();
		for(int i = 2; i <= n; i++){
			int u,v,w;
			scanf("%d%d%d",&u,&v,&w);
			g[u].push_back(edge{v,w});
			g[v].push_back(edge{u,w});
		}
		dfs(1,0);
		ll ans = 1e11;
		for(int i = 0; i <= 2*m; i+=2)
			ans = min(ans,dp[1][i]+1ll*i/2*k);
		printf("%lld\n",ans);
	} 
	return 0;
}

E.Fisherman

#include
using namespace std;
typedef long long ll;
#define lowbit(x) x&(-x)
const int mx = 3e5+5;
struct point{
	ll x,y,val;
	bool operator<(const point &a)const{
		return x=q[i].val&&j<=n){
			int k = lower_bound(x+1,x+n,a[j].val)-x;
			add(k);
			j++;
		}
		int k = upper_bound(x+1,x+n+1,l+q[i].val)-x;
		k--;
		ans[q[i].id] += query(k);
	}
	for(int i = 1; i <= m; i++)
		printf("%d\n",ans[i]);
	return 0;
}

F.Min Max Convert

一个结论就是要么左更新,要么右更新,左更新从右到左,右更新从左到右,而且不互相包含。而且把一个区间变成一个端点的值最多只要操作两次

#include
#define x first 
#define y second
using namespace std;
typedef unsigned long long ull;
typedef pair pa; 
const int mx = 1e5 + 10;
int n,m;
int a[mx],b[mx];
vector  g[2];
struct node {
	char ch;
	int l,r;
}s[mx<<1]; 
bool solve() {
	int siz = 0;
	for (int i=1,j=1;i<=n;i++) {
		while (j <= n && a[j] != b[i]) j++;
		if (j == n+1) return 0*puts("-1");
		if (i < j) g[0].push_back(pa(i,j));
		if (i > j) g[1].push_back(pa(j,i)); 
	}
	int pre = 0;
	for (int i=0;i= a[r]) s[siz++] = {'m',now.x,now.y};
		else {
			s[siz++] = {'m',now.x,now.y-1};
			s[siz++] = {'M',now.x,now.y};
		}
	}
	pre = 1e6;
	for (int i=g[1].size()-1;i>=0;i--) {
		pa now = g[1][i];
		int r = min(now.y,pre), l = now.x;
		int mi =  1e7, ma = -1;
		if (l == r) continue;
		while (l < r) {
			mi = min(mi,a[r]);
			ma = max(ma,a[r--]);
		}
		pre = now.x;
		if (ma <= a[r]) s[siz++] = {'M',now.x,now.y};
		else if (mi >= a[r]) s[siz++] = {'m',now.x,now.y};
		else {
			s[siz++] = {'m',now.x+1,now.y};
			s[siz++] = {'M',now.x,now.y};
		}
	}
	printf("%d\n",siz);
	for (int i=0;i

G.Matrix Queries

待做

H.Modern Djinn

待做

I.Inversion

代码丢了,应该是dp求路径个数

J.Rabbit vs Turtle

读懂题目基本就会了,主要是要注意如果路径下一跳是在最短路径上是不能作弊的

#include 
using namespace std;
typedef long long ll;
const int mx = 1e5 + 10;
int n,m;
int p_t,p_r;
int a[mx],b[mx];
int ans[mx],siz;
ll c[mx],suf[mx],dis[mx];
struct node {
	int u,v;
	int T,R;
}s[mx<<1]; 
vector  g[mx];
bool vis[mx];
void spfa(int beg) {
	queue  q;
	q.push(beg);
	for (int i=1;i<=n;i++) 
		dis[i] = 1e16;
	dis[beg] = 0;
	while (!q.empty()) {
		int u = q.front();
		q.pop();
		vis[u] = 0;
		for (int idx : g[u]) {
			node now = s[idx];
			int v = now.u; // 反向边 
			if (dis[v] > dis[u] + now.R) {
				dis[v] = dis[u] + now.R;
				if (!vis[v]) {
					vis[v] = 1;
					q.push(v);
				}
			} 
		}
	}
}
int main()
{
	scanf("%d%d",&n,&m);
	int u,v,T,R;
	for (int i=1;i<=m;i++) {
		scanf("%d%d%d%d",&u,&v,&T,&R);
		s[i] = {u,v,T,R};
		g[v].push_back(i);
	}
	scanf("%d",&p_t);
	for (int i=1;i<=p_t;i++) {
		scanf("%d%lld",a+i,c+i);
	}
	for (int i=p_t;i>=1;i--)
		suf[i] = suf[i+1] + s[a[i]].T;
	scanf("%d",&p_r);
	for (int i=1;i<=p_r;i++) 
		scanf("%d",b+i);
	spfa(n);
	ll r_time = 0,t_time = 0;
	for (int i=1,j=1;i<=p_r;i++) {
		while (j <= p_t && t_time + s[a[j]].T <= r_time) {
			t_time += s[a[j]].T + c[j];
			j++;
		}
		if (dis[s[b[i]].u] == dis[s[b[i]].v] + s[b[i]].R) {
			r_time += s[b[i]].R;
			continue;
		}
		if (r_time + dis[s[b[i]].u] <= t_time + suf[j])
			ans[siz++] = s[b[i]].u;
		r_time += s[b[i]].R;
	}
	sort(ans,ans+siz);
	printf("%d\n",siz);
	for (int i=0;i

K.Points and Rectangles

CDQ分治,不过这题麻烦就在于,矩形和点要分开计算,可以合在一起不过就是常数大了一倍,而且点计算矩形和矩形计算点的方式也不太一样

#include 
using namespace std;
const int mx = 8e5 + 50;
typedef long long ll;
struct node {
	int x,y;
	int v,id;
	bool operator < (node A) const {
		return x < A.x;
	}
}s[mx],tmp[mx];
int siz,n,b[mx],tot;
int sum1[mx],dp[mx],sum2[mx];
void add(int x,int v,int* sum) {
	for(;x> 1;
	cdq_divide(l,mid);
	for (int i=l;i<=r;i++) tmp[i] = s[i];
	sort(tmp+l,tmp+mid+1);
	sort(tmp+mid+1,tmp+r+1);
	int i = l,j = mid + 1;
	while (j <= r) {
		if (i <= mid && tmp[i].x <= tmp[j].x) {
			if (!tmp[i].v) add(tmp[i].y,1,sum1);
			if (tmp[i].id<0) add(tmp[i].y,tmp[i].v,sum2);
			i++;
		} else {
			if (tmp[j].id>0) {
				if (tmp[j].v)
					dp[tmp[j].id] += tmp[j].v*get_sum(tmp[j].y,sum1);
				else 
					dp[tmp[j].id] += get_sum(tmp[j].y,sum2);
			}
			j++;
		}
	}
	for (i=l;i<=mid&&tmp[i].x<=tmp[r].x;i++) {
		if (!tmp[i].v) add(tmp[i].y,-1,sum1);
		if (tmp[i].id<0) add(tmp[i].y,-tmp[i].v,sum2);
	}
	cdq_divide(mid+1,r);
}
int main() {
	//freopen("1.in","r",stdin);
	scanf("%d",&n);
	for (int i=1;i<=n;i++) {
		int c,x1,x2,y1,y2;
		scanf("%d",&c);
		if (c == 1) {
			scanf("%d%d",&x1,&y1);
			b[++tot] = y1;
			s[++siz] = {x1,y1,0,i};
		} else {
			scanf("%d%d%d%d",&x1,&y1,&x2,&y2);
			s[++siz] = {x2,y2,1,i};
			s[++siz] = {x1,y1,1,-i};
			
			s[++siz] = {x1-1,y1-1,1,i};
			s[++siz] = {x2+1,y2+1,1,-i};
			
			s[++siz] = {x1-1,y2,-1,i};
			s[++siz] = {x1,y2+1,-1,-i};
			
			s[++siz] = {x2,y1-1,-1,i};
			s[++siz] = {x2+1,y1,-1,-i};
			
			b[++tot] = y2,b[++tot] = y2+1;
			b[++tot] = y1,b[++tot] = y1-1;
		}
	}
	sort(b+1,b+1+tot);
	tot = unique(b+1,b+1+tot) - b;
	for (int i=1;i<=siz;i++)
		s[i].y = lower_bound(b+1,b+tot,s[i].y) - b;
	cdq_divide(1,siz);
	ll ans = 0;
	for (int i=1;i<=n;i++) {
		ans += dp[i];
		printf("%lld\n",ans);
	}
	return 0;
}

 

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