标签：style blog http color io strong for 数据 2014
话说比较简单.除了第三题不会写平衡树啊你妹!!边做边写吧.
仍然是机智的链接
题目的数据范围非常小,来个 大法狮 吧.$6^6$只有$46656$,加上浮点运算的超大常数也不多嘛 ╮(╯_╰)╭
实现有点恶心,暴力你懂得.
#include <cstdio>
#include <cmath>
#define PI 3.1415926535897932384626
inline double ab(double x){
return (((x)>=0)?(x):(-x));
}
inline double mi(double x,double y){
y=ab(y);
return (x<y?x:y);
}
inline double ma(double x,double y){
y=ab(y);
return (x>y?x:y);
}
int n;
double x[8],y[8],r[8],s[8],minLeft;
bool f[8];
void dfs(int p,int d,double si){
double a,b,c;
int i;
b=ab(x[p]-x[0]);
b=mi(b,x[p]-x[1]);
b=mi(b,y[p]-y[1]);
b=mi(b,y[p]-y[0]);
for(i=2;i<=n;++i){
if(f[i]) b=mi(b,hypot(x[p]-x[i],y[p]-y[i])-r[i]);
}
f[p]=true;
si+=PI*b*b;
r[p]=b;
if(d==n-1){
si=s[0]-si;
if(si<minLeft){
minLeft=si;
}
r[p]=0.0;
f[p]=false;
return;
}
for(i=2;i<=n;++i){
if(!f[i]){
dfs(i,d+1,si);
}
}
r[p]=0.0;
f[p]=false;
}
int main(){
freopen("box2.in","r",stdin);
freopen("box2.out","w",stdout);
scanf("%d%lf%lf%lf%lf",&n,x,y,x+1,y+1);
minLeft=s[0]=s[1]=ab((x[1]-x[0])*(y[1]-y[0]));
++n;
int i;
for(i=2;i<=n;++i) scanf("%lf%lf",x+i,y+i);
for(i=2;i<=n;++i){
dfs(i,1,0.0);
}
printf("%.0lf",minLeft);
return 0;
}
~!~!@~!@@!@!##@@#@!@##@@@#@#%^&^%##@!@@我是机智的分割线~~~
简单的动规.DP方程:
DP F[i,j]=max(F[i-1,j]+same(c[i],i-j),F[i-1,j-1])
# F[i,j]表示前i个数删去j个的最大匹配数,c[i]表示第i个数字
# same(a,b)=(a==b?1:0)
return MaxAmong(F,lengthof F)
#include <cstdio>
int f[2000][2000],c[2000],n,i,j;
inline int max(int a,int b){
return a>b?a:b;
}
int main(){
freopen("sequence.in","r",stdin);
freopen("sequence.out","w",stdout);
scanf("%d",&n);
for(i=1;i<=n;++i){
scanf("%d",c+i);
}
for(i=1;i<=n;++i){
for(j=0;j<=i;++j){
f[i][j]=max(f[i-1][j]+(c[i]==i-j),f[i-1][j-1]);
}
}
j=0;
for(i=0;i<=n;++i){
if(f[n][i]>j) j=f[n][i];
}
printf("%d\n",j);
return 0;
}
真的很 短啊.
不会写BST啊神犇滚粗!!!
好吧今天边学习边写,应该SBT比较方便实现吧.
标签：style blog http color io strong for 数据 2014
原文地址：http://www.cnblogs.com/tmzbot/p/3969324.html
