题目链接:http://poj.org/problem?id=2926
题意:求5维空间的点集中的最远曼哈顿距离。。
降维处理,推荐2009武森《浅谈信息学竞赛中的“0”和“1”》以及《论一类平面点对曼哈顿距离问题》。
1 //STATUS:C++_AC_735MS_184KB 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 //#pragma comment(linker,"/STACK:102400000,102400000") 25 //using namespace __gnu_cxx; 26 //define 27 #define pii pair<int,int> 28 #define mem(a,b) memset(a,b,sizeof(a)) 29 #define lson l,mid,rt<<1 30 #define rson mid+1,r,rt<<1|1 31 #define PI acos(-1.0) 32 //typedef 33 typedef __int64 LL; 34 typedef unsigned __int64 ULL; 35 //const 36 const int N=50010; 37 const int INF=0x3f3f3f3f; 38 //const LL MOD=1000000007,STA=8000010; 39 const LL LNF=1LL<<55; 40 const double EPS=1e-9; 41 const double OO=1e50; 42 const int dx[4]={-1,0,1,0}; 43 const int dy[4]={0,1,0,-1}; 44 const int day[13]={0,31,28,31,30,31,30,31,31,30,31,30,31}; 45 //Daily Use ... 46 inline int sign(double x){return (x>EPS)-(x<-EPS);} 47 template<class T> T gcd(T a,T b){return b?gcd(b,a%b):a;} 48 template<class T> T lcm(T a,T b){return a/gcd(a,b)*b;} 49 template<class T> inline T lcm(T a,T b,T d){return a/d*b;} 50 template<class T> inline T Min(T a,T b){return a<b?a:b;} 51 template<class T> inline T Max(T a,T b){return a>b?a:b;} 52 template<class T> inline T Min(T a,T b,T c){return min(min(a, b),c);} 53 template<class T> inline T Max(T a,T b,T c){return max(max(a, b),c);} 54 template<class T> inline T Min(T a,T b,T c,T d){return min(min(a, b),min(c,d));} 55 template<class T> inline T Max(T a,T b,T c,T d){return max(max(a, b),max(c,d));} 56 //End 57 58 double x[5],low[32],hig[32]; 59 int n; 60 61 int main(){ 62 // freopen("in.txt","r",stdin); 63 int i,j,k; 64 double ans,sum; 65 while(~scanf("%d",&n)) 66 { 67 for(i=0;i<32;i++){ 68 low[i]=OO; 69 hig[i]=-OO; 70 } 71 for(i=0;i<n;i++){ 72 scanf("%lf%lf%lf%lf%lf",&x[0],&x[1],&x[2],&x[3],&x[4]); 73 for(j=0;j<32;j++){ 74 sum=0; 75 for(k=0;k<5;k++){ 76 sum+=(j&(1<<k)?x[k]:-x[k]); 77 } 78 low[j]=Min(low[j],sum); 79 hig[j]=Max(hig[j],sum); 80 } 81 } 82 ans=0; 83 for(i=0;i<32;i++){ 84 ans=Max(ans,hig[i]-low[i]); 85 } 86 87 printf("%.2lf ",ans); 88 } 89 return 0; 90 }