Treap初步
模板题
bzoj3224: Tyvj 1728 普通平衡树
1 #include <bits/stdc++.h> 2 #define rep(i, a, b) for (int i = a; i <= b; i++) 3 #define REP(i, a, b) for (int i = a; i < b; i++) 4 #define drep(i, a, b) for (int i = a; i >= b; i--) 5 #define pb push_back 6 #define mp make_pair 7 #define xx first 8 #define yy second 9 using namespace std; 10 typedef long long i64; 11 typedef pair<int, int> pii; 12 const int inf = ~0U >> 1; 13 const i64 INF = ~0ULL >> 1; 14 //***************************** 15 16 const int maxn = 100005; 17 struct node { 18 int l, r, v, w, sz, rnd; 19 node () { l = r = v = w = sz = rnd = 0; } 20 } tr[maxn]; 21 int ndtot, root, ans; 22 23 int read() { 24 int l = 1, s(0); char ch = getchar_unlocked(); 25 while (ch < '0' || ch > '9') { if (ch == '-') l = -1; ch = getchar_unlocked(); } 26 while (ch >= '0' && ch <= '9') { s = (s << 1) + (s << 3) + ch - '0'; ch = getchar_unlocked(); } 27 return l * s; 28 } 29 30 void update(int &k) { tr[k].sz = tr[tr[k].l].sz + tr[k].w + tr[tr[k].r].sz; } 31 32 void lturn(int &k) { 33 int t = tr[k].r; tr[k].r = tr[t].l; tr[t].l = k; 34 tr[t].sz = tr[k].sz; update(k); k = t; 35 } 36 37 void rturn(int &k) { 38 int t = tr[k].l; tr[k].l = tr[t].r; tr[t].r = k; 39 tr[t].sz = tr[k].sz; update(k); k = t; 40 } 41 42 void insrt(int &k, int x) { 43 if (k == 0) { 44 k = ++ndtot; 45 tr[k].sz = tr[k].w = 1, tr[k].v = x, tr[k].rnd = rand(); 46 return; 47 } 48 tr[k].sz++; 49 if (tr[k].v == x) tr[k].w++; 50 else if (x > tr[k].v) { 51 insrt(tr[k].r, x); 52 if (tr[tr[k].r].rnd < tr[k].rnd) lturn(k); 53 } 54 else { 55 insrt(tr[k].l, x); 56 if (tr[tr[k].l].rnd < tr[k].rnd) rturn(k); 57 } 58 } 59 60 void del(int &k, int x) { 61 if (k == 0) return; 62 if (tr[k].v == x) { 63 if (tr[k].w > 1) { 64 tr[k].w--; tr[k].sz--; return; 65 } 66 if (tr[k].l * tr[k].r == 0) k = tr[k].l + tr[k].r; 67 else if (tr[tr[k].l].rnd < tr[tr[k].r].rnd) rturn(k), del(k, x); 68 else lturn(k), del(k, x); 69 } 70 else if (x > tr[k].v) tr[k].sz--, del(tr[k].r, x); 71 else tr[k].sz--, del(tr[k].l, x); 72 } 73 74 int query_rnk(int k, int x) { 75 if (k == 0) return 0; 76 if (tr[k].v == x) return tr[tr[k].l].sz + 1; 77 else if (x > tr[k].v) return tr[tr[k].l].sz + tr[k].w + query_rnk(tr[k].r, x); 78 else return query_rnk(tr[k].l, x); 79 } 80 81 int query_num(int k, int x) { 82 if (k == 0) return 0; 83 if (x <= tr[tr[k].l].sz) return query_num(tr[k].l, x); 84 else if (x > tr[tr[k].l].sz + tr[k].w) return query_num(tr[k].r, x - tr[tr[k].l].sz - tr[k].w); 85 else return tr[k].v; 86 } 87 88 void query_pre(int k, int x) { 89 if (k == 0) return; 90 if (x > tr[k].v) { 91 ans = tr[k].v; query_pre(tr[k].r, x); 92 } 93 else query_pre(tr[k].l, x); 94 } 95 96 void query_sub(int k, int x) { 97 if (k == 0) return; 98 if (x < tr[k].v) { 99 ans = tr[k].v; query_sub(tr[k].l, x); 100 } 101 else query_sub(tr[k].r, x); 102 } 103 104 int main() { 105 int n; n = read(); 106 while (n--) { 107 int op, x; op = read(), x = read(); 108 switch(op) { 109 case 1: insrt(root, x); break; 110 case 2: del(root, x); break; 111 case 3: printf("%d\n", query_rnk(root, x)); break; 112 case 4: printf("%d\n", query_num(root, x)); break; 113 case 5: ans = 0; query_pre(root, x); printf("%d\n", ans); break; 114 case 6: ans = 0; query_sub(root, x); printf("%d\n", ans); break; 115 } 116 } 117 }
bzoj1503: 郁闷的出纳员
按理来说Treap保持平衡后是不能旋转的，然而这个题乱搞A了，把要查询的点旋转到根上然后干掉。。
1 #include <bits/stdc++.h> 2 #define rep(i, a, b) for (int i = a; i <= b; i++) 3 #define REP(i, a, b) for (int i = a; i < b; i++) 4 #define drep(i, a, b) for (int i = a; i >= b; i--) 5 #define mp make_pair 6 #define pb push_back 7 #define clr(x) memset(x, 0, sizeof(x)) 8 #define xx first 9 #define yy second 10 using namespace std; 11 typedef long long i64; 12 const int inf = ~0U>>1; 13 const i64 INF = ~0ULL>>1; 14 //**************************** 15 16 const int maxn = 100005; 17 18 struct node { 19 int l, r, v, rnd, w, sz; 20 node() { l = r = v = rnd = w = sz = 0; } 21 } tr[maxn]; 22 int ndtot, root; 23 void update(int k) { tr[k].sz = tr[tr[k].l].sz + tr[k].w + tr[tr[k].r].sz; } 24 void lturn(int &k) { 25 int t = tr[k].r; tr[k].r = tr[t].l; tr[t].l = k; 26 tr[t].sz = tr[k].sz; update(k); k = t; 27 } 28 void rturn(int &k) { 29 int t = tr[k].l; tr[k].l = tr[t].r; tr[t].r = k; 30 tr[t].sz = tr[k].sz; update(k); k = t; 31 } 32 33 void insrt(int &k, int x) { 34 if (!k) { 35 k = ++ndtot; 36 tr[k].v = x, tr[k].rnd = rand(), tr[k].w = tr[k].sz = 1; 37 return; 38 } 39 tr[k].sz++; 40 if (tr[k].v == x) tr[k].w++; 41 else if (x > tr[k].v) { 42 insrt(tr[k].r, x); 43 if (tr[tr[k].r].rnd < tr[k].rnd) lturn(k); 44 } 45 else if (x < tr[k].v) { 46 insrt(tr[k].l, x); 47 if (tr[tr[k].l].rnd < tr[k].rnd) rturn(k); 48 } 49 } 50 51 int query_num(int &k, int x) { 52 if (!k) return 0; 53 if (x <= tr[tr[k].l].sz) return query_num(tr[k].l, x); 54 else if (x > tr[tr[k].l].sz + tr[k].w) return query_num(tr[k].r, x - tr[tr[k].l].sz - tr[k].w); 55 else return tr[k].v; 56 } 57 58 void fix(int &k, int x) { 59 if (!k) return; 60 if (tr[k].v >= x) { 61 fix(tr[k].l, x); 62 if (tr[k].l && tr[tr[k].l].v >= x) rturn(k); 63 } 64 else { 65 fix(tr[k].r, x); 66 if (tr[k].r && tr[tr[k].r].v >= x) lturn(k); 67 } 68 } 69 70 char str[5]; 71 int main() { 72 int n, m; 73 scanf("%d%d", &n, &m); 74 int tot(0); 75 int be(0); 76 insrt(root, 0x3f3f3f3f); 77 while (n--) { 78 int x; 79 scanf("%s%d", str, &x); 80 if (str[0] == 'I') { if (x >= m) insrt(root, x - tot), be++; } 81 else if (str[0] == 'A') tot += x; 82 else if (str[0] == 'S') { 83 tot -= x; 84 fix(root, m - tot); 85 tr[root].sz -= tr[tr[root].l].sz; 86 tr[tr[root].l] = node(); 87 tr[root].l = 0; 88 } 89 else { 90 if (x + 1 > tr[root].sz) puts("-1"); 91 else printf("%d\n", query_num(root, tr[root].sz - x) + tot); 92 } 93 } 94 printf("%d\n", be - tr[root].sz + 1); 95 return 0; 96 }
