USACO 5.5 Picture(周长并)

POJ最近做过的原题。

  1 /*
  2  ID: cuizhe
  3  LANG: C++
  4  TASK: picture
  5 */
  6 #include <cstdio>
  7 #include <cstring>
  8 #include <string>
  9 #include <cmath>
 10 #include <algorithm>
 11 using namespace std;
 12 #define maxn 10000
 13 #define lson l , m, rt<<1
 14 #define rson m+1, r,rt<<1|1
 15 int que[maxn*4];
 16 int sum[maxn*4];
 17 int cnt[maxn*4];
 18 bool lbd[maxn*4] , rbd[maxn*4];
 19 int numseg[maxn*4];
 20 struct node
 21 {
 22     int lx,rx,y;
 23     int s;
 24     node() {}
 25     node(int a,int b,int c,int d):lx(a),rx(b),y(c),s(d) {}
 26     bool operator < (const node &S) const
 27     {
 28         if(y == S.y) return s > S.s;
 29         return y < S.y;
 30     }
 31 } mat[maxn];
 32 int bin(int x,int n)
 33 {
 34     int str,end,mid;
 35     str = 0,end = n;
 36     while(str <= end)
 37     {
 38         mid = (str+end)/2;
 39         if(que[mid] == x)
 40             return mid;
 41         else if(que[mid] > x)
 42             end = mid - 1;
 43         else
 44             str = mid + 1;
 45     }
 46     return mid;
 47 }
 48 void pushup(int rt,int l,int r)
 49 {
 50     if(cnt[rt])
 51     {
 52         lbd[rt] = rbd[rt] = 1;
 53         sum[rt] = que[r+1] - que[l];
 54         numseg[rt] = 2;
 55     }
 56     else if (l == r)
 57     {
 58         sum[rt] = numseg[rt] = lbd[rt] = rbd[rt] = 0;
 59     }
 60     else
 61     {
 62         lbd[rt] = lbd[rt<<1];
 63         rbd[rt] = rbd[rt<<1|1];
 64         sum[rt] = sum[rt<<1] + sum[rt<<1|1];
 65         numseg[rt] = numseg[rt<<1] + numseg[rt<<1|1];
 66         if (lbd[rt<<1|1] && rbd[rt<<1]) numseg[rt] -= 2;
 67     }
 68 }
 69 void update(int L,int R,int c,int l,int r,int rt)
 70 {
 71     if(L <= l&&r <= R)
 72     {
 73         cnt[rt] += c;
 74         pushup(rt,l,r);
 75         return ;
 76     }
 77     int m = (l+r)>>1;
 78     if(L <= m)
 79         update(L,R,c,lson);
 80     if(R > m)
 81         update(L,R,c,rson);
 82     pushup(rt,l,r);
 83 }
 84 int main()
 85 {
 86     int n,num,i,l,r;
 87     int a,b,c,d;
 88     freopen("picture.in","r",stdin);
 89     freopen("picture.out","w",stdout);
 90     while(scanf("%d",&n)!=EOF)
 91     {
 92         if(!n) break;
 93         num = 0;
 94         for(i = 0; i < n; i ++)
 95         {
 96             scanf("%d%d%d%d",&a,&b,&c,&d);
 97             que[num] = a;
 98             mat[num ++] = node(a,c,b,1);
 99             que[num] = c;
100             mat[num ++] = node(a,c,d,-1);
101         }
102         sort(que,que+num);
103         sort(mat,mat+num);
104         int k = 1;
105         for(i = 1; i < num; i ++)
106         {
107             if(que[i] != que[i-1])
108                 que[k++] = que[i];
109         }
110         int ans = 0,last = 0;
111         memset(cnt,0,sizeof(cnt));
112         memset(sum,0,sizeof(sum));
113         memset(lbd,0,sizeof(lbd));
114         memset(rbd,0,sizeof(rbd));
115         for(i = 0; i < num; i ++)
116         {
117             l = bin(mat[i].lx,k-1);
118             r = bin(mat[i].rx,k-1)-1;
119             if(l <= r)
120                 update(l,r,mat[i].s,0,k-1,1);
121             ans += numseg[1] * (mat[i+1].y - mat[i].y);
122             ans += abs(sum[1] - last);
123             last = sum[1];
124         }
125         printf("%d\n",ans);
126     }
127     return 0;
128 }

 

posted @ 2013-08-19 17:46  Naix_x  阅读(188)  评论(0)  编辑  收藏  举报