Picture 1828
http://acm.hdu.edu.cn/showproblem.php?pid=1828
求矩形的周长
1 #include <iostream> 2 #include <cstdio> 3 #include <algorithm> 4 #define lson l,mid,i<<1 5 #define rson mid+1,r,i<<1|1 6 using namespace std; 7 const int Ni = 40100; 8 struct node{ 9 int l,r,h,s; 10 node(){} 11 node(int a,int b,int c,int d):l(a),r(b),h(c),s(d){} 12 bool operator < (const node &a) const 13 { 14 if(h==a.h) return s > a.s; 15 return h < a.h; 16 } 17 }arr[Ni]; 18 int sum[Ni*3]; 19 int num[Ni*3]; 20 int cnt[Ni*3]; 21 int lbd[Ni*3]; 22 int rbd[Ni*3]; 23 void build(int l,int r,int i) 24 { 25 sum[i]=num[i]=cnt[i]=0; 26 lbd[i]=rbd[i]=0; 27 if(l==r) return; 28 int mid=(l+r)>>1; 29 build(lson); 30 build(rson); 31 } 32 void pushup(int l,int r,int i) 33 { 34 if (cnt[i]) { 35 lbd[i] = rbd[i] = 1; 36 sum[i] = r - l + 1; 37 num[i] = 2; 38 } else if (l == r) { 39 sum[i] = num[i] = lbd[i] = rbd[i] = 0; 40 } else { 41 lbd[i] = lbd[i<<1]; 42 rbd[i] = rbd[i<<1|1]; 43 sum[i] = sum[i<<1] + sum[i<<1|1]; 44 num[i] = num[i<<1] + num[i<<1|1]; 45 if (lbd[i<<1|1] && rbd[i<<1]) num[i] -= 2; 46 } 47 } 48 void update(int ql,int qr,int s,int l,int r,int i=1) 49 { 50 if(ql<=l&&r<qr) 51 { 52 cnt[i]+=s; 53 pushup(l,r,i); 54 return; 55 } 56 int mid=(l+r)>>1; 57 if(ql<=mid) update(ql,qr,s,lson); 58 if(qr>mid+1) update(ql,qr,s,rson); 59 pushup(l,r,i); 60 } 61 int main() 62 { 63 int n,m,i; 64 while(cin>>n) 65 { 66 m=0; 67 int l=100000,r=-100000; 68 for(i=0;i<n;i++) 69 { 70 int a,b,c,d; 71 scanf("%d%d%d%d",&a,&b,&c,&d); 72 l=min(l,a); 73 r=max(r,c); 74 arr[m++]=node(a,c,b,1); 75 arr[m++]=node(a,c,d,-1); 76 } 77 sort(arr,arr+m); 78 build(l,r,1); 79 int ret=0,last=0; 80 for(i=0;i<m;i++) 81 { 82 update(arr[i].l,arr[i].r,arr[i].s,l,r); 83 ret+=num[1]*(arr[i+1].h-arr[i].h); 84 ret+=abs(sum[1]-last); 85 last=sum[1]; 86 } 87 printf("%d\n",ret); 88 } 89 return 0; 90 }
