瘋狂的WA
最後還是得參考網路,原來是要一直更新左邊跟右邊
//============================================================================
// Name : How Big Is It.cpp
// Date : 2013/4/26 下午1:30:18
// Author : GCA
//============================================================================
#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <climits>
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <cctype>
#include <utility>
using namespace std;
#ifdef ONLINE_JUDGE
#define ll "%lld"
#else
#define ll "%I64d"
#endif
typedef unsigned int uint;
typedef long long int Int;
#define Set(a,s) memset(a,s,sizeof(a))
#define Write(w) freopen(w,"w",stdout)
#define Read(r) freopen(r,"r",stdin)
#define Pln() printf("\n")
#define I_de(x,n)for(int i=0;i<n;i++)printf("%d ",x[i]);Pln()
#define De(x)printf(#x"%d\n",x)
#define For(i,x)for(int i=0;i<x;i++)
#define CON(x,y) x##y
#define Pmz(dp,nx,ny)for(int hty=0;hty<ny;hty++){for(int htx=0;htx<nx;htx++){\
printf("%d ",dp[htx][hty]);}Pln();}
#define M 55
#define PII pair<int,int>
#define PB push_back
#define oo INT_MAX
#define Set_oo 0x3f
#define Is_debug true
#define debug(...) if(Is_debug)printf("DEBUG: "),printf(__VA_ARGS__)
#define FOR(it,c) for(__typeof((c).begin()) it=(c).begin();it!=(c).end();it++)
#define eps 1e-6
bool xdy(double x,double y){return x>y+eps;}
bool xddy(double x,double y){return x>y-eps;}
bool xcy(double x,double y){return x<y-eps;}
bool xcdy(double x,double y){return x<y+eps;}
int min3(int x,int y,int z){
int tmp=min(x,y);
return min(tmp,z);
}
int max3(int x,int y,int z){
int tmp=max(x,y);
return max(tmp,z);
}
double r[M];
bool vis[M];
double pos[M];
double dfsr[M];
double minans;
int n;
void dfs(int depth){
if(depth==n){
double xl=oo;
double xr=0;
for(int i=0;i<n;i++){
xl=min(xl,(pos[i]-dfsr[i]));
xr=max(xr,(pos[i]+dfsr[i]));
}
minans=min(minans,xr-xl);
return;
}
for(int i=0;i<n;i++){
if(!vis[i]){
dfsr[depth]=r[i];
pos[depth]=0;
for(int j=0;j<depth;j++){
double c=dfsr[j]+r[i];
double a=fabs(dfsr[j]-r[i]);
double b=sqrt(c*c-a*a);
pos[depth]=max(pos[depth],b+pos[j]);
}
vis[i]=1;
dfs(depth+1);
vis[i]=0;
}
}
}
int main() {
ios_base::sync_with_stdio(0);
int test;
scanf("%d",&test);
while(test--){
scanf("%d",&n);
for(int i=0;i<n;i++)scanf("%lf",&r[i]);
Set(vis,0);
minans=oo;
for(int i=0;i<n;i++){
dfsr[0]=r[i];
pos[0]=r[i];
vis[i]=1;
dfs(1);
vis[i]=0;
}
printf("%.3f\n",minans);
}
}
留言
張貼留言