20240418

2024-04-18 18:38:55 +08:00
parent bfcbb1996a
commit 4f8f929242
20 changed files with 3408 additions and 0 deletions
--- a/ACMOJ-2163.cpp
+++ b/ACMOJ-2163.cpp
@ -0,0 +1,36 @@
+#include <algorithm>
+#include <cstdio>
+#include <cstring>
+#include <iostream>
+using namespace std;
+typedef long long LL;
+typedef long double LDB;
+const int kMaxN = 1e5 + 10;
+int n, key[kMaxN], w[kMaxN];
+int stk[kMaxN], ls[kMaxN], rs[kMaxN];
+void dfs(int rt) {
+  printf("%d ", rt);
+  if (ls[rt]) dfs(ls[rt]);
+  if (rs[rt]) dfs(rs[rt]);
+}
+int main() {
+#ifdef local
+  freopen("pro.in", "r", stdin);
+#endif
+  scanf("%d", &n);
+  for (int i = 1; i <= n; i++) {
+    scanf("%d", &key[i]);
+    w[key[i]] = i;
+  }
+  int top = 0;
+  for (int i = 1; i <= n; i++) {
+    int k = top;
+    while (k > 0 && w[stk[k]] > w[i]) k--;
+    if (k) rs[stk[k]] = i;  // rs代表笛卡尔树每个节点的右儿子
+    if (k < top) ls[i] = stk[k + 1];  // ls代表笛卡尔树每个节点的左儿子
+    stk[++k] = i;
+    top = k;
+  }
+  dfs(stk[1]);
+  return 0;
+}