第一种AC:95%,错误一个测试点

#include<set>
#include<cstdio>
#include<algorithm>
#define db double
#define U unsigned
#define ll long long
#define lb long double
#define ull unsigned long long
#define Me(a,b) memset(a,b,sizeof(a))
template<typename _T> _T abs(_T a){ return a>0?a:-a; }
template<typename _T> _T max(_T a,_T b){ return a>b?a:b; }
template<typename _T> _T min(_T a,_T b){ return a<b?a:b; }
template<typename _T> void print(_T x){ if(x<0) putchar('-'),x=-x;
	if(x>9) print(x/10); putchar(x%10+48); return; }
#define EPS (1e-7)
#define INF (0x7fffffff)
#define LLINF (0x7fffffffffffffff)
#define maxn 100039
#define maxm
#define MOD
using namespace std;
#define Type int
Type read(){
	char c=getchar(); Type sum=0; int flag=0;
	while((c<'0'||c>'9')&&c!='-') c=getchar(); if(c=='-') c=getchar(),flag=1;
	while('0'<=c&&c<='9'){ sum=(sum<<1)+(sum<<3)+(c^48); c=getchar(); }
	if(flag) return -sum; return sum;
}
int n,m1,m2,f1[maxn],f2[maxn];
struct Plane{
	int st,en,num;
	bool operator < (const Plane x) const{ return this->st < x.st; }
}a1[maxn],a2[maxn];
int cmp(Plane x,Plane y){ return x.st<y.st; }
set<Plane> s; int flag[maxn];
void init(Plane a[],int f[],int m){
	s.clear(); int i,now=0; Plane tmp; set<Plane>::iterator it; for(i=1;i<=m;i++) s.insert(a[i]);
	while(!s.empty()){
		tmp=*s.begin(); s.erase(s.begin()); now++; f[now]=1;
		while(1){
			tmp.st=tmp.en; it=s.upper_bound(tmp);
			if(it==s.end()) break; f[now]++; s.erase(it); tmp=*it;
		}
	} return;
}
int maxx;
int main(){
	//freopen("airport.in","r",stdin);
	//freopen(".out","w",stdout);
	n=read(); m1=read(); m2=read(); int i;
	for(i=1;i<=m1;i++) a1[i].st=read(),a1[i].en=read(),a1[i].num=i; init(a1,f1,m1);
	for(i=1;i<=m2;i++) a2[i].st=read(),a2[i].en=read(),a2[i].num=i; init(a2,f2,m2);
	//for(i=1;i<=m1;i++) print(f1[i]),putchar(' '); putchar('\n');
	//for(i=1;i<=m1;i++) print(f2[i]),putchar(' '); putchar('\n');
	for(i=1;i<=m1;i++) f1[i]+=f1[i-1]; for(i=1;i<=m2;i++) f2[i]+=f2[i-1];
	for(i=0;i<=n;i++) if(f1[i]+f2[n-i]>maxx) maxx=f1[i]+f2[n-i];
	print(maxx); return 0;
}

换种思路重新定义 AC:100%(accept)

#include <bits/stdc++.h>
#include <cstdio>
#include <functional>
#define P pair <int,int>
using namespace std;

struct node {
	int a, b;
} fc[100010], fa[100010];

bool cmp(node a, node b) {
	return a.a < b.a;
}
int n, m1, m2, maxn = -1, ans1[100010], ans2[100010];

void check() {
	priority_queue<int, vector<int>, greater<int> > q;//维护廊桥编号
	priority_queue<P, vector<P>, greater<P> > p;//维护飞机出站时间和停靠的廊桥的编号
	for (int i = 1; i <= n; i++) {
		q.push(i);//一开始所有廊桥都处于空闲状态，把所有廊桥加入队列。
	}
	for (int i = 1; i <= m1; i++) {
		int s = fc[i].a;//该架飞机入站时间
		while (!p.empty() && s > p.top().first) {
			//弹出已经飞走的飞机并把它所停课的廊桥加入队列
			q.push(p.top().second);
			p.pop();
		}
		if (!q.empty()) {
			int id = q.top();
			q.pop();//取编号最小的廊桥停靠
			ans1[id]++;//该编号的廊桥产生的贡献加一
			p.push(P(fc[i].b, id));
		}
	}
	while (!q.empty())
		q.pop();
	while (!p.empty())
		p.pop();
	//清空队列
	for (int i = 1; i <= n; i++) {
		q.push(i);
	}
	//同上
	for (int i = 1; i <= m2; i++) {
		int s = fa[i].a;
		while (!p.empty() && s > p.top().first) {
			q.push(p.top().second);
			p.pop();
		}
		if (!q.empty()) {
			int id = q.top();
			q.pop();
			ans2[id]++;
			p.push(P(fa[i].b, id));
		}
	}
	for (int i = 1; i <= n; i++) {
		ans1[i] += ans1[i - 1];
		ans2[i] += ans2[i - 1];
	}
	//前缀和数组维护每种分配方案产生的答案
	return;
}

int main() {
	scanf("%d%d%d", &n, &m1, &m2);
	for (int i = 1; i <= m1; i++) {
		scanf("%d%d", &fc[i].a, &fc[i].b);
	}
	for (int i = 1; i <= m2; i++) {
		scanf("%d%d", &fa[i].a, &fa[i].b);
	}
	sort(fc + 1, fc + 1 + m1, cmp);
	sort(fa + 1, fa + 1 + m2, cmp);
	check();
	//统计答案
	for (int i = 0; i <= n; i++) {
		if (ans1[i] + ans2[n - i] > maxn) {
			maxn = ans1[i] + ans2[n - i];
		}
	}
	printf("%d", maxn);
	return 0;
}