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 }