首先做这题的时候,题目就吸引了我,梦三国这游戏正好在玩!!!
题意:有n名游戏玩家,现在有m个服务器,每个服务器能服务区间[l:r]里面的人,并且有人数限制
问你如何安排使得游戏玩家同时在线人数尽可能多?
分析:
首先,我们肯定是编号小的塞到前面的区间,把当前编号的人塞到右区间靠前的区间里,这里我们用优先队列
来实现,优先队列里的排序规则先按照右端点小的排序,再按照服务器承载人数小的来排序。 读入的区间我们也需要排序,按照左区间、右区间、区间承载人数依次排序即可。
最后从编号为1的游戏玩家开始遍历到n的游戏玩家,每次需要需要再队列头判断,当前游戏玩家编号是不是大于队列顶端的r值,如果大于,说明当前队列头的这个区间不可能包含了,直接pop。 每次弹出一个值,我们只需要把对应人数--。这样就做到了最贪的分配了。
大佬们有的用网络流来实现,本弱还不会。。。。
AC代码:
/** * ┏┓ ┏┓ * ┏┛┗━━━━━━━┛┗━━━┓ * ┃ ┃ * ┃ ━ ┃ * ┃ > < ┃ * ┃ ┃ * ┃... ⌒ ... ┃ * ┃ ┃ * ┗━┓ ┏━┛ * ┃ ┃ Code is far away from bug with the animal protecting * ┃ ┃ 神兽保佑,代码无bug * ┃ ┃ * ┃ ┃ * ┃ ┃ * ┃ ┃ * ┃ ┗━━━┓ * ┃ ┣┓ * ┃ ┏┛ * ┗┓┓┏━━━━━━━━┳┓┏┛ * ┃┫┫ ┃┫┫ * ┗┻┛ ┗┻┛ */ #pragma GCC optimize(1) #pragma GCC optimize(2) #pragma GCC optimize(3) #pragma GCC optimize("Ofast") #pragma GCC optimize("inline") #pragma GCC optimize("-fgcse") #pragma GCC optimize("-fgcse-lm") #pragma GCC optimize("-fipa-sra") #pragma GCC optimize("-ftree-pre") #pragma GCC optimize("-ftree-vrp") #pragma GCC optimize("-fpeephole2") #pragma GCC optimize("-ffast-math") #pragma GCC optimize("-fsched-spec") #pragma GCC optimize("unroll-loops") #pragma GCC optimize("-falign-jumps") #pragma GCC optimize("-falign-loops") #pragma GCC optimize("-falign-labels") #pragma GCC optimize("-fdevirtualize") #pragma GCC optimize("-fcaller-saves") #pragma GCC optimize("-fcrossjumping") #pragma GCC optimize("-fthread-jumps") #pragma GCC optimize("-funroll-loops") #pragma GCC optimize("-fwhole-program") #pragma GCC optimize("-freorder-blocks") #pragma GCC optimize("-fschedule-insns") #pragma GCC optimize("inline-functions") #pragma GCC optimize("-ftree-tail-merge") #pragma GCC optimize("-fschedule-insns2") #pragma GCC optimize("-fstrict-aliasing") #pragma GCC optimize("-fstrict-overflow") #pragma GCC optimize("-falign-functions") #pragma GCC optimize("-fcse-skip-blocks") #pragma GCC optimize("-fcse-follow-jumps") #pragma GCC optimize("-fsched-interblock") #pragma GCC optimize("-fpartial-inlining") #pragma GCC optimize("no-stack-protector") #pragma GCC optimize("-freorder-functions") #pragma GCC optimize("-findirect-inlining") #pragma GCC optimize("-frerun-cse-after-loop") #pragma GCC optimize("inline-small-functions") #pragma GCC optimize("-finline-small-functions") #pragma GCC optimize("-ftree-switch-conversion") #pragma GCC optimize("-foptimize-sibling-calls") #pragma GCC optimize("-fexpensive-optimizations") #pragma GCC optimize("-funsafe-loop-optimizations") #pragma GCC optimize("inline-functions-called-once") #pragma GCC optimize("-fdelete-null-pointer-checks") #pragma G++ optimize(1) #pragma G++ optimize(2) #pragma G++ optimize(3) #pragma G++ optimize("Ofast") #pragma G++ optimize("inline") #pragma G++ optimize("-fgcse") #pragma G++ optimize("-fgcse-lm") #pragma G++ optimize("-fipa-sra") #pragma G++ optimize("-ftree-pre") #pragma G++ optimize("-ftree-vrp") #pragma G++ optimize("-fpeephole2") #pragma G++ optimize("-ffast-math") #pragma G++ optimize("-fsched-spec") #pragma G++ optimize("unroll-loops") #pragma G++ optimize("-falign-jumps") #pragma G++ optimize("-falign-loops") #pragma G++ optimize("-falign-labels") #pragma G++ optimize("-fdevirtualize") #pragma G++ optimize("-fcaller-saves") #pragma G++ optimize("-fcrossjumping") #pragma G++ optimize("-fthread-jumps") #pragma G++ optimize("-funroll-loops") #pragma G++ optimize("-fwhole-program") #pragma G++ optimize("-freorder-blocks") #pragma G++ optimize("-fschedule-insns") #pragma G++ optimize("inline-functions") #pragma G++ optimize("-ftree-tail-merge") #pragma G++ optimize("-fschedule-insns2") #pragma G++ optimize("-fstrict-aliasing") #pragma G++ optimize("-fstrict-overflow") #pragma G++ optimize("-falign-functions") #pragma G++ optimize("-fcse-skip-blocks") #pragma G++ optimize("-fcse-follow-jumps") #pragma G++ optimize("-fsched-interblock") #pragma G++ optimize("-fpartial-inlining") #pragma G++ optimize("no-stack-protector") #pragma G++ optimize("-freorder-functions") #pragma G++ optimize("-findirect-inlining") #pragma G++ optimize("-frerun-cse-after-loop") #pragma G++ optimize("inline-small-functions") #pragma G++ optimize("-finline-small-functions") #pragma G++ optimize("-ftree-switch-conversion") #pragma G++ optimize("-foptimize-sibling-calls") #pragma G++ optimize("-fexpensive-optimizations") #pragma G++ optimize("-funsafe-loop-optimizations") #pragma G++ optimize("inline-functions-called-once") #pragma G++ optimize("-fdelete-null-pointer-checks") #include <iostream> #include <algorithm> #include <cstdio> #include <cstring> #include <string> #include <vector> #include <map> #include <queue> #include <deque> #include <set> #include <stack> #include <cctype> #include <cmath> #include <cassert> #define IOS ios::sync_with_stdio(0); cin.tie(0); cout.tie(0); #define INF 0x3f3f3f3f #define PI 3.14159265358979323846 #define esp 1e-8 //#define int long long using namespace std; typedef long long ll; typedef pair<int, int> pii; typedef pair<ll, ll> pll; const ll mod=1000000007; ll powmod(ll a,ll b) {ll res=1;a%=mod; assert(b>=0); for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;} ll gcd(ll a,ll b) { return b?gcd(b,a%b):a;} int dir[4][2]={{0,-1},{-1,0},{0,1},{1,0}}; int dir2[8][2]={{-1,-1},{-1,1},{1,-1},{1,1},{0,-1},{-1,0},{0,1},{1,0}}; template <typename _T> inline void read(_T &f) { f = 0; _T fu = 1; char c = getchar(); while (c < '0' || c > '9') { if (c == '-') { fu = -1; } c = getchar(); } while (c >= '0' && c <= '9') { f = (f << 3) + (f << 1) + (c & 15); c = getchar(); } f *= fu; } template <typename T> void print(T x) { if (x < 0) putchar('-'), x = -x; if (x < 10) putchar(x + 48); else print(x / 10), putchar(x % 10 + 48); } template <typename T> void print(T x, char t) { print(x); putchar(t); } const int N=10000+100; int n,m; struct Node { int l,r,ct; }a[N]; bool cmp(Node _,Node __) { if(_.l!=__.l) { return _.l<__.l; } else { if(_.r!=__.r) { return _.r<__.r; } else { return _.ct<__.ct; } } } struct node { int r,ct; friend bool operator <(struct node x,struct node y) { if(x.r!=y.r)return x.r>y.r; else return x.ct>y.ct; } }; int main() { while(~scanf("%d%d",&n,&m)) { priority_queue<pii,vector<pii>,greater<pii> >p; for(int i=1;i<=m;i++) { scanf("%d%d%d",&a[i].l,&a[i].r,&a[i].ct); } sort(a+1,a+1+m,cmp); int ans=0; int bh=1; for(int i=1;i<=n;i++) { while(!p.empty()&&p.top().first<i)p.pop(); while(a[bh].l==i) { p.push({a[bh].r,a[bh].ct}); bh++; } if(p.empty())continue; pii t=p.top(); p.pop(); ans++; t.second--; if(t.second>0)p.push(t); } printf("%d\n",ans); } return 0; }