Oh those picky N (1 <= N <= 50,000) cows! They are so picky that each one will only be milked over some precise time interval A..B (1 <= A <= B <= 1,000,000), which includes both times A and B. Obviously, FJ must create a reservation system to determine which stall each cow can be assigned for her milking time. Of course, no cow will share such a private moment with other cows.
Help FJ by determining:
- The minimum number of stalls required in the barn so that each cow can have her private milking period
- An assignment of cows to these stalls over time
Many answers are correct for each test dataset; a program will grade your answer.
Input
Line 1: A single integer, N
Lines 2..N+1: Line i+1 describes cow i's milking interval with two space-separated integers.
Output
Line 1: The minimum number of stalls the barn must have.
Lines 2..N+1: Line i+1 describes the stall to which cow i will be assigned for her milking period.
Sample Input
5
1 10
2 4
3 6
5 8
4 7
Sample Output
4
1
2
3
2
4
Hint
Explanation of the sample:
Here's a graphical schedule for this output:
Time 1 2 3 4 5 6 7 8 9 10
Stall 1 c1>>>>>>>>>>>>>>>>>>>>>>>>>>>
Stall 2 .. c2>>>>>> c4>>>>>>>>> .. ..
Stall 3 .. .. c3>>>>>>>>> .. .. .. ..
Stall 4 .. .. .. c5>>>>>>>>> .. .. ..
Other outputs using the same number of stalls are possible.
题意:给出每个奶牛挤奶的时间段,一个机器一次只能对一头奶牛工作,问至少需要多少台机器,并输出每头奶牛使用的机器编号。
#include <iostream>
#include <cstdio>
#include <cmath>
#include <algorithm>
#include <cstring>
#include <vector>
#include <map>
#include <stack>
#include <queue>
#define rush() int T;cin>>T;while(T--)
#define go(a) while(cin>>a)
#define ms(a,b) memset(a,b,sizeof a)
#define E 1e-8
using namespace std;
typedef __int64 ll;
const int idata=1e5+5;
int n,m,t,_;
int i,j,k;
int cnt,num;
int minn,maxx;
struct Node
{
int st,e;
int id;
const bool operator<(const Node & b)
const{
return e>b.e;//结束时间早的在队首
}
}node[idata];
priority_queue<Node>q;
bool cmp(Node a,Node b)
{
return a.st==b.st ? a.e<b.e : a.st<b.st;
}
int ans[idata];
void clear()
{
priority_queue<Node>temp;
swap(temp,q);
return ;
}
int main()
{
cin.tie(0);
iostream::sync_with_stdio(false);
while(cin>>n)
{
Node temp;
for(i=1;i<=n;i++){
cin>>node[i].st>>node[i].e;
node[i].id=i;
}
sort(node+1,node+1+n,cmp);
clear();
num=0;
q.push(node[1]);
ans[ node[1].id ]=++num;
for(i=2;i<=n;i++){
if(!q.empty() && q.top().e<node[i].st ){
temp=q.top();
q.pop();
ans[ node[i].id ]=ans[ temp.id ];
}
else ans[ node[i].id ]=++num;
q.push(node[i]);
}
cout<<num<<endl;
for(i=1;i<=n;i++){
cout<<ans[i]<<endl;
}
}
return 0;
}