ZOJ-3721 Final Exam Arrangement 贪心
题目链接：http://acm.zju.edu.cn/onlinejudge/showProblem.do?problemCode=3721
容易的贪心题，排个序。。
1 //STATUS:C++_AC_840MS_6272KB 2 #include <functional> 3 #include <algorithm> 4 #include <iostream> 5 //#include <ext/rope> 6 #include <fstream> 7 #include <sstream> 8 #include <iomanip> 9 #include <numeric> 10 #include <cstring> 11 #include <cassert> 12 #include <cstdio> 13 #include <string> 14 #include <vector> 15 #include <bitset> 16 #include <queue> 17 #include <stack> 18 #include <cmath> 19 #include <ctime> 20 #include <list> 21 #include <set> 22 #include <map> 23 using namespace std; 24 //using namespace __gnu_cxx; 25 //define 26 #define pii pair<int,int> 27 #define mem(a,b) memset(a,b,sizeof(a)) 28 #define lson l,mid,rt<<1 29 #define rson mid+1,r,rt<<1|1 30 #define PI acos(-1.0) 31 //typedef 32 //typedef __int64 LL; 33 //typedef unsigned __int64 ULL; 34 //const 35 const int N=100010; 36 const int INF=0x3f3f3f3f; 37 const int MOD=100000,STA=8000010; 38 //const LL LNF=1LL<<60; 39 const double EPS=1e-8; 40 const double OO=1e15; 41 const int dx[4]={-1,0,1,0}; 42 const int dy[4]={0,1,0,-1}; 43 const int day[13]={0,31,28,31,30,31,30,31,31,30,31,30,31}; 44 //Daily Use ... 45 inline int sign(double x){return (x>EPS)-(x<-EPS);} 46 template<class T> T gcd(T a,T b){return b?gcd(b,a%b):a;} 47 template<class T> T lcm(T a,T b){return a/gcd(a,b)*b;} 48 template<class T> inline T lcm(T a,T b,T d){return a/d*b;} 49 template<class T> inline T Min(T a,T b){return a<b?a:b;} 50 template<class T> inline T Max(T a,T b){return a>b?a:b;} 51 template<class T> inline T Min(T a,T b,T c){return min(min(a, b),c);} 52 template<class T> inline T Max(T a,T b,T c){return max(max(a, b),c);} 53 template<class T> inline T Min(T a,T b,T c,T d){return min(min(a, b),min(c,d));} 54 template<class T> inline T Max(T a,T b,T c,T d){return max(max(a, b),max(c,d));} 55 //End 56 57 struct Node{ 58 int l,r; 59 int idx; 60 bool operator < (const Node &a)const { 61 return l!=a.l?l<a.l:r<a.r; 62 } 63 }p[N]; 64 int cnt[N]; 65 vector<int> q[N]; 66 int n; 67 68 int main() 69 { 70 // freopen("in.txt","r",stdin); 71 int i,j,tot,R; 72 while(~scanf("%d",&n)) 73 { 74 tot=0; 75 mem(cnt,0); 76 for(i=0;i<=n;i++)q[i].clear(); 77 for(i=0;i<n;i++){ 78 scanf("%d%d",&p[i].l,&p[i].r); 79 p[i].idx=i+1; 80 } 81 sort(p,p+n); 82 83 R=-1; 84 for(i=0;i<n;i++){ 85 if(p[i].l>=R){ 86 tot++; 87 R=p[i].r; 88 } 89 R=Min(R,p[i].r); 90 q[tot].push_back(p[i].idx); 91 cnt[tot]++; 92 } 93 94 printf("%d\n",tot); 95 for(i=1;i<=tot;i++){ 96 printf("%d",q[i][0]); 97 for(j=1;j<cnt[i];j++) 98 printf(" %d",q[i][j]); 99 putchar('\n'); 100 } 101 putchar('\n'); 102 } 103 return 0; 104 }
