http://poj.org/problem?id=3580
给一个长度为N(N<10,000)的数列，要求支持6种操作： 1. 将区间[l,r]同时加一个数 2. 将区间[l,r]翻转 3.将区间[l,r]旋转若干次 4. 插入一个数 5. 删除一个数 6.求[l,r]的最小值
对于操作1,懒惰标记。
操作2,懒惰标记。如果不懂如何维护就看我上一篇题解...
操作3，交换两区间。因为两区间是相临的[a,b] [b+1,c]，那么先把a-1旋到树根，再旋b，再旋c，然后大家知道怎么做了吧....
什么？ 还不知道，在纸上画画吧...
操作4 & 5, 基本操作。
操作6， 维护一个min值，维护方法和size相同。
trick:
1. 旋转若干次可能是很多次
2. 旋转0次
1 #include <cstdio> 2 #include <cstring> 3 #include <iostream> 4 #include <algorithm> 5 using namespace std; 6 #define inf (1<<29) 7 const int maxn = 200020; 8 int nowsz , splaysz; 9 struct node { 10 int p,chd[2],mn,sz,rt,ad,val; 11 }tree[maxn]; 12 inline void sc(int y,int x,int p) { tree[y].chd[p]=x;tree[x].p=y; } 13 inline void pushdown(int x) { 14 if(!x) return; 15 if(tree[x].rt) { 16 tree[x].rt ^= 1; 17 swap(tree[x].chd[0] , tree[x].chd[1]); 18 tree[tree[x].chd[0]].rt ^= 1; 19 tree[tree[x].chd[1]].rt ^= 1; 20 } 21 if(tree[x].ad) { 22 tree[x].mn += tree[x].ad; 23 tree[x].val += tree[x].ad; 24 tree[tree[x].chd[0]].ad += tree[x].ad; 25 tree[tree[x].chd[1]].ad += tree[x].ad; 26 tree[x].ad = 0; 27 } 28 } 29 inline void update(int x) { 30 if(!x) return; 31 pushdown(tree[x].chd[0]); 32 pushdown(tree[x].chd[1]); 33 tree[x].mn = tree[x].val; 34 tree[x].mn = min( tree[x].mn , min( tree[tree[x].chd[0]].mn , tree[tree[x].chd[1]].mn ) ); 35 tree[x].sz = tree[tree[x].chd[0]].sz + tree[tree[x].chd[1]].sz + 1; 36 } 37 inline void rot(int x) { 38 int y = tree[x].p; 39 int w = tree[y].chd[1] == x; 40 sc(tree[y].p,x,tree[tree[y].p].chd[1]==y); 41 sc(y,tree[x].chd[w^1],w); 42 sc(x,y,w^1); 43 update(y); 44 update(x); 45 } 46 void dfs(int x) { 47 if(!x) return; 48 dfs(tree[x].p); 49 pushdown(x); 50 } 51 void splay(int x,int rt=0) { 52 if(x == rt || x == 0) return; 53 dfs(x); 54 while(tree[x].p!=rt) { 55 int y = tree[x].p; 56 int w = tree[y].chd[1]==x; 57 if(tree[y].p != rt && tree[tree[y].p].chd[w]==y) rot(y); 58 rot(x); 59 } 60 } 61 int find(int val) { 62 if(val == 0 || val >= nowsz) return 0; 63 int x = tree[0].chd[1]; 64 while(1) { 65 pushdown(x); 66 int u = tree[x].chd[0]; 67 int v = tree[x].chd[1]; 68 if(tree[u].sz + 1 == val) return x; 69 else if(tree[u].sz + 1 > val) x = u; 70 else { 71 x = v; 72 val -= tree[u].sz + 1; 73 } 74 } 75 } 76 int query(int l,int r,char cmd[],int val=0) { 77 int u = find(l) , v =find(r); 78 if(u) splay(u); 79 if(v) splay(v , u); 80 if(!strcmp(cmd,"DELETE")) { 81 if(v == 0) { tree[u].chd[1]=0; update(u); } 82 else { tree[v].chd[0]=0; splay(v); } 83 nowsz --; 84 } 85 else if(!strcmp(cmd,"INSERT")) { 86 node &now = tree[splaysz]; 87 now.ad = now.rt = 0; 88 now.mn = now.val = val; 89 now.chd[0] = now.chd[1] = 0; 90 if(v == 0 && u == 0) { 91 //assert(tree[0].chd[1]==0); 92 sc(0,splaysz,1); 93 } 94 else if(v == 0) sc(u,splaysz,1); 95 else sc(v,splaysz,0); 96 splaysz ++; nowsz ++; 97 splay(splaysz-1); 98 } 99 else if(!strcmp(cmd,"REVOLVE")) { 100 int p = find(val); 101 if(p) splay(p,v); 102 sc(u,p,1); 103 sc(v,tree[p].chd[1],1); 104 sc(p,v,1); 105 update(v); update(p); 106 } 107 else { 108 int x = 0; 109 if(v == 0) x = tree[u].chd[1]; 110 else { 111 x = tree[v].chd[0]; splay(v); 112 } 113 //assert(x); 114 int ans = tree[x].mn; 115 if(!strcmp(cmd,"ADD")) tree[x].ad += val; 116 if(!strcmp(cmd,"REVERSE")) tree[x].rt ^= 1; 117 splay(x , 0); 118 if(!strcmp(cmd,"MIN")) return ans; 119 } 120 } 121 int main() { 122 int n,m,x,y,z,ans; 123 char cmd[11]; 124 tree[0].chd[0] = tree[0].chd[1] = tree[0].sz = 0; 125 tree[0].mn = inf; 126 scanf("%d" , &n); 127 for(int i=1;i<=n;i++) { 128 scanf("%d",&tree[i].val); 129 tree[i].chd[0] = tree[i].chd[1] = 0; 130 tree[i].mn = tree[i].val; 131 sc(i-1 , i , 1); 132 splay(i); 133 } 134 splaysz = nowsz = n + 1; 135 scanf("%d" , &m); 136 while(m--) { 137 scanf("%s" , cmd); 138 if(!strcmp(cmd,"ADD")) { 139 scanf("%d%d%d",&x,&y,&z); 140 query(x-1,y+1,cmd,z); 141 } 142 else if(!strcmp(cmd,"REVERSE")) { 143 scanf("%d%d",&x,&y); 144 query(x-1,y+1,cmd); 145 } 146 else if(!strcmp(cmd,"REVOLVE")) { 147 scanf("%d%d%d",&x,&y,&z); 148 z %= (y-x+1); if(!z) continue; 149 query(x-1,y-z,cmd,y); 150 } 151 else if(!strcmp(cmd,"INSERT")) { 152 scanf("%d%d",&x,&y); 153 query(x,x+1,cmd,y); 154 } 155 else if(!strcmp(cmd,"INSERT")) { 156 scanf("%d%d",&x,&y); 157 query(x,x+1,cmd,y); 158 } 159 else if(!strcmp(cmd,"MIN")) { 160 scanf("%d%d",&x,&y); 161 ans = query(x-1,y+1,cmd); 162 printf("%d\n" , ans); 163 } 164 else { 165 scanf("%d",&x); 166 query(x-1,x+1,cmd); 167 } 168 } 169 return 0; 170 }
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