【HDU4391】【块状链表】Paint The Wall

  1 #include <iostream>
  2 #include <cstdio>
  3 #include <algorithm>
  4 #include <cstring>
  5 #include <vector>
  6 #include <utility>
  7 #include <iomanip>
  8 #include <string>
  9 #include <cmath>
 10 #include <queue>
 11 #include <assert.h>
 12 #include <map>
 13 
 14 const int N = 100000 + 10;
 15 using namespace std;
 16 int n, c, data[N];
 17 int SIZE;
 18 map<int, int>color[334];
 19 
 20 void change2(int l,int r){
 21     int x = l / SIZE;
 22     if(color[x].size() == 1){//整个块只有一个颜色 
 23         map<int, int>::iterator it = color[x].begin();
 24         int last = it->first, cnt = it->second;
 25         if(c == last) return ;//显然等于原来的颜色就没必要修改了 
 26         if(r - l + 1 == cnt){//整个块都修改 
 27             color[x][c] = r - l + 1;
 28             color[x].erase(it);
 29             return;
 30         }
 31         for(int i = SIZE * x; i < n && i < SIZE * ( x + 1 ); i++){
 32             if(i >= l && i <= r) data[i] = c;
 33             else data[i] = last;
 34         }
 35         color[x][c] = r - l + 1;
 36         color[x][last] = cnt - (r - l + 1);
 37     }else 
 38     for(int i = l; i <= r; i++) {//进行直接修改 
 39         if(data[i] == c) continue;
 40         map<int, int>::iterator it = color[x].find(data[i]);
 41         if(it->second == 1) color[x].erase(it);//记住一定要删除不然会超空间 
 42         else it->second--;
 43         color[x][c]++;
 44         data[i] = c;
 45     }
 46 }
 47 //注意这种带2的操作是在同一个块内操作的 
 48 int query2(int l,int r){
 49     int x = l / SIZE;
 50     if(color[x].count(c)){
 51         if(color[x].size() == 1) return r - l + 1;//整块的颜色唯一 
 52         else{
 53             int cnt = 0;
 54             for(int i = l; i <= r; i++) if(data[i] == c) cnt++;
 55             return cnt;
 56         }
 57     } else return 0;
 58 }
 59 
 60 void change(int l,int r){
 61     int x1 = l / SIZE, x2 = r / SIZE;
 62     if(x1 == x2){change2(l, r);return;}
 63     change2(l, SIZE * (x1 + 1) - 1);
 64     change2(SIZE * x2, r);
 65     //真正无奈 
 66     for(int i = x1 + 1; i < x2; i++){
 67         color[i].clear();
 68         color[i][c] = SIZE;
 69     }
 70 }
 71 
 72 int query(int l,int r){
 73     int x1 = l / SIZE, x2 = r / SIZE;
 74     if(x1 == x2) return query2(l,r);
 75     int Ans = query2(l, SIZE * (x1 + 1) - 1) + query2(SIZE * x2 ,r);
 76     for(int i = x1 + 1;i < x2;i++)
 77     if(color[i].count(c)) Ans += color[i][c];
 78     return Ans;
 79 }
 80 
 81 void init(){
 82     SIZE = (int)sqrt(n * 1.0);
 83     for(int i = 0; i < n; i++) scanf("%d", &data[i]);
 84     for(int i = 0; i <= n / SIZE; i++) color[i].clear();
 85     for(int i = 0; i < n; i++) {
 86         int tmp = i / SIZE;
 87         color[tmp][ data[i] ]++;
 88     }
 89 }
 90 
 91 int main(){
 92     #ifdef LOCAL
 93     freopen("data.txt",  "r",  stdin);
 94     freopen("out.txt",  "w",  stdout); 
 95     #endif
 96     int m;
 97     while(scanf("%d%d",&n,&m) != EOF){         
 98         init();                
 99         for (int i = 1; i <= m; i++){
100             int t, l, r;
101             scanf("%d%d%d%d", &t, &l, &r, &c);
102             if(t == 1) change(l,r);
103             else printf("%d\n",query(l,r));
104         }
105     }
106     return 0;
107 }