1019.Line Painting(线段树 离散化）

1019

离散化都忘记怎么写了 注意两个端点 离散化后用线段树更新区间 混色为-1  黑为2  白为1  因为N不大 最后直接循环标记这一段的颜色查找

  1 #include <iostream>

  2 #include<cstdio>

  3 #include<cstring>

  4 #include<algorithm>

  5 #include<stdlib.h>

  6 using namespace std;

  7 #define N 100010

  8 #define LL long long

  9 struct node

 10 {

 11     int d,id;

 12     char c;

 13 }li[N<<1];

 14 int q[N][3],pp[N];

 15 int s[N<<2],cnt[N],cc[N];

 16 void build(int l,int r,int w)

 17 {

 18     s[w] = 1;

 19     if(l==r-1)

 20     {

 21         return ;

 22     }

 23     int m = (l+r)>>1;

 24     build(l,m,w<<1);

 25     build(m,r,w<<1|1);

 26 }

 27 void update(int a,int b,int d,int l,int r,int w)

 28 {

 29     if(a<=l&&b>=r)

 30     {

 31         s[w] = d;

 32         return ;

 33     }

 34     if(l==r-1)

 35     return ;

 36     if(s[w]>0&&s[w]!=d)

 37     {

 38         s[w<<1] = s[w<<1|1] = s[w];

 39         s[w] = -1;

 40     }

 41     int m = (l+r)>>1;

 42     if(a<=m)

 43     update(a,b,d,l,m,w<<1);

 44     if(b>m)

 45     update(a,b,d,m,r,w<<1|1);

 46 }

 47 void query(int l,int r,int w)

 48 {

 49     int i;

 50     if(s[w]>0)

 51     {

 52         for(i = l ; i < r; i++)

 53         cnt[i] = s[w];

 54         return ;

 55     }

 56     if(l==r-1)

 57     return ;

 58     int m = (l+r)>>1;

 59     query(l,m,w<<1);

 60     query(m,r,w<<1|1);

 61 }

 62 bool cmp(node a,node b)

 63 {

 64     return a.d<b.d;

 65 }

 66 int main()

 67 {

 68     int i,n;

 69     char c[10];

 70     scanf("%d",&n);

 71     for(i = 0 ; i < n ; i++)

 72     {

 73         scanf("%d%d%s",&q[i][0],&q[i][1],c);

 74         if(c[0]=='b')

 75         cc[i+1] = 2;

 76         else

 77         cc[i+1] = 1;

 78         li[2*i].d = q[i][0];

 79         li[2*i].id = -(i+1);

 80         li[2*i+1].d = q[i][1];

 81         li[2*i+1].id = i+1;

 82     }

 83     sort(li,li+2*n,cmp);

 84     int tt = li[0].d,g=1;

 85     for(i = 0 ; i < 2*n ; i++)

 86     {

 87         if(li[i].d!=tt)

 88         {

 89             g++;

 90             tt = li[i].d;

 91         }

 92         if(li[i].id<0)

 93         {

 94             q[-li[i].id][0] = g;

 95             pp[g] = li[i].d;

 96         }

 97         else

 98         {

 99             q[li[i].id][1] = g;

100             pp[g] = li[i].d;

101         }

102     }

103     build(0,g,1);

104     for(i = 0; i <= g ; i++)

105     cnt[i] = 1;

106     for(i = 1 ; i <= n ; i++)

107     {

108         update(q[i][0],q[i][1],cc[i],0,g,1);

109     }

110     query(0,g,1);

111     int maxz=0,ss,ee,ts,te;

112     cnt[0] = 1;

113     cnt[g+1] = 1;

114     pp[g+1] = 1000000000;

115     for(i = 0 ; i <= g ; i++)

116     {

117         if(cnt[i]!=1)

118         continue;

119         ss = pp[i];

120         while(cnt[i]==1&&i<=g)

121         i++;

122         ee = pp[i];

123         if(ee-ss+1>maxz)

124         {

125             ts = ss;

126             te = ee;

127             maxz = ee-ss+1;

128         }

129     }

130     printf("%d %d\n",ts,te);

131     return 0;

132 }

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