[POJ2777]Count Color（线段树）

题目链接：http://poj.org/problem?id=2777

给你一个长为L想线段，向上面染色，颜色不超过３０种，一共有Ｏ次操作，操作有两种：

C a b c　在[a,b]上染上c颜色

P a b　查询[a,b]上所有颜色数。

 

思路：线段树维护每个线段上颜色种类，用位来存颜色。好题。

  1 /*
  2 ━━━━━┒ギリギリ♂ eye！
  3 ┓┏┓┏┓┃キリキリ♂ mind！
  4 ┛┗┛┗┛┃＼○／
  5 ┓┏┓┏┓┃ /
  6 ┛┗┛┗┛┃ノ)
  7 ┓┏┓┏┓┃
  8 ┛┗┛┗┛┃
  9 ┓┏┓┏┓┃
 10 ┛┗┛┗┛┃
 11 ┓┏┓┏┓┃
 12 ┛┗┛┗┛┃
 13 ┓┏┓┏┓┃
 14 ┃┃┃┃┃┃
 15 ┻┻┻┻┻┻
 16 */
 17 #include <algorithm>
 18 #include <iostream>
 19 #include <iomanip>
 20 #include <cstring>
 21 #include <climits>
 22 #include <complex>
 23 #include <fstream>
 24 #include <cassert>
 25 #include <cstdio>
 26 #include <bitset>
 27 #include <vector>
 28 #include <deque>
 29 #include <queue>
 30 #include <stack>
 31 #include <ctime>
 32 #include <set>
 33 #include <map>
 34 #include <cmath>
 35 using namespace std;
 36 #define fr first
 37 #define sc second
 38 #define cl clear
 39 #define BUG puts("here!!!")
 40 #define W(a) while(a--)
 41 #define pb(a) push_back(a)
 42 #define Rint(a) scanf("%d", &(a))
 43 #define Rll(a) scanf("%I64d", &a)
 44 #define Rs(a) scanf("%s", a)
 45 #define Cin(a) cin >> a
 46 #define FRead() freopen("in", "r", stdin)
 47 #define FWrite() freopen("out", "w", stdout)
 48 #define Rep(i, len) for(int i = 0; i < (len); i++)
 49 #define For(i, a, len) for(int i = (a); i < (len); i++)
 50 #define Cls(a) memset((a), 0, sizeof(a))
 51 #define Clr(a, x) memset((a), (x), sizeof(a))
 52 #define Full(a) memset((a), 0x7f, sizeof(a))
 53 #define lrt rt << 1
 54 #define rrt rt << 1 | 1
 55 #define pi 3.14159265359
 56 #define RT return
 57 #define lowbit(x) x & (-x)
 58 #define onenum(x) __builtin_popcount(x)
 59 typedef long long LL;
 60 typedef long double LD;
 61 typedef unsigned long long Uint;
 62 typedef pair<int, int> pii;
 63 typedef pair<LL, LL> pLL;
 64 typedef pair<string, LL> psi;
 65 typedef map<string, LL> msi;
 66 typedef vector<LL> vi;
 67 typedef vector<LL> vl;
 68 typedef vector<vl> vvl;
 69 typedef vector<bool> vb;
 70 
 71 #define lson l, m, rt << 1
 72 #define rson m + 1, r, rt << 1 | 1
 73 const int maxn = 100010;
 74 int sum[maxn<<2];
 75 int add[maxn<<2];
 76 int L, T, O;
 77 
 78 void pushUP(int rt) {
 79     sum[rt] = sum[lrt] | sum[rrt];
 80 }
 81 
 82 void pushDOWN(int rt) {
 83     if(add[rt] != -1) {
 84         sum[lrt] = sum[rrt] = (1 << add[rt]);
 85         add[lrt] = add[rrt] = add[rt];
 86         add[rt] = -1;
 87     }
 88 }
 89 
 90 void build(int l, int r, int rt) {
 91     sum[rt] = 1; add[rt] = 1;
 92     if(l == r) return;
 93     int m = (l + r) >> 1;
 94     build(l, m, lrt);
 95     build(m+1, r, rrt);
 96 }
 97 
 98 void update(int L, int R, int c, int l, int r, int rt) {
 99     if(L <= l && r <= R) {
100         add[rt] = c;
101         sum[rt] = 1 << c;
102         return;
103     }
104     pushDOWN(rt);
105     int m = (l + r) >> 1;
106     if(L <= m) update(L, R, c, lson);
107     if(m < R) update(L, R, c, rson);
108     pushUP(rt);
109 }
110 
111 int query(int L, int R, int l, int r, int rt) {
112     if(L <= l && r <= R) return sum[rt];
113     pushDOWN(rt);
114     int m = (l + r) >> 1;
115     int ret = 0;
116     if(L <= m) ret |= query(L, R, lson);
117     if(m < R) ret |= query(L, R, rson);
118     return ret;
119 }
120 
121 int main() {
122 //    FRead();
123     char cmd[2];
124     int l, r, c;
125     while(~scanf("%d%d%d", &L, &T, &O)) {
126         build(1, L, 1);
127         W(O) {
128             Rs(cmd);
129             if(cmd[0] == 'C') {
130                 scanf("%d%d%d",&l,&r,&c);
131                 if(l > r) swap(l, r);
132                 update(l, r, c, 1, L, 1);
133             }
134             else {
135                 scanf("%d%d",&l,&r);
136                 if(l > r) swap(l, r);
137                 int p = query(l, r, 1, L, 1);
138                 int ret = 0;
139                 while(p) {
140                     if(p & 1) ret++;
141                     p >>= 1;
142                 }
143                 printf("%d\n", ret);
144             }
145         }
146     }
147     RT 0;
148 }

 

posted @ 2016-08-08 19:35  Kirai  阅读(189)  评论(0)  编辑  收藏  举报