modify code

Author: algorithmzuo

src/class166/Code01_SegmentTreeDivideAndConquer1.java

@@ -113,7 +113,7 @@ public static void dfs(int l, int r, int i) {
 		}
 	}
 
-	public static void main(String[] args) throws IOException {
+	public static void main(String[] args) {
 		FastIO io = new FastIO(System.in, System.out);
 		n = io.nextInt();
 		m = io.nextInt();

src/class166/Code02_MinimumMexTree1.java

@@ -109,7 +109,7 @@ public static int dfs(int l, int r, int i) {
 		return ans;
 	}
 
-	public static void main(String[] args) throws IOException {
+	public static void main(String[] args) {
 		FastIO io = new FastIO(System.in, System.out);
 		n = io.nextInt();
 		m = io.nextInt();

src/class166/Code03_UniqueOccurrences1.java

@@ -0,0 +1,217 @@
+package class166;
+
+// 独特事件，java版
+// 测试链接 : https://www.luogu.com.cn/problem/CF1681F
+// 测试链接 : https://codeforces.com/problemset/problem/1681/F
+// 提交以下的code，提交时请把类名改成"Main"，可以通过所有测试用例
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+public class Code03_UniqueOccurrences1 {
+
+	public static int MAXN = 500001;
+	public static int MAXT = 10000001;
+	public static int n, m;
+
+	public static int[] x = new int[MAXN];
+	public static int[] y = new int[MAXN];
+	public static int[] c = new int[MAXN];
+
+	public static int[] father = new int[MAXN];
+	public static int[] siz = new int[MAXN];
+	public static int[][] rollback = new int[MAXN][2];
+	public static int opsize;
+
+	public static int[] headc = new int[MAXN];
+	public static int[] nextc = new int[MAXN];
+	public static int[] toc = new int[MAXN];
+	public static int cntc = 0;
+
+	public static int[] heads = new int[MAXT];
+	public static int[] nexts = new int[MAXT];
+	public static int[] tos = new int[MAXT];
+	public static int cnts = 0;
+
+	public static long ans = 0;
+
+	public static void addEdgeC(int u, int v) {
+		nextc[++cntc] = headc[u];
+		toc[cntc] = v;
+		headc[u] = cntc;
+	}
+
+	public static void addEdgeS(int u, int v) {
+		nexts[++cnts] = heads[u];
+		tos[cnts] = v;
+		heads[u] = cnts;
+	}
+
+	public static int find(int i) {
+		while (i != father[i]) {
+			i = father[i];
+		}
+		return i;
+	}
+
+	public static void union(int x, int y) {
+		int fx = find(x);
+		int fy = find(y);
+		if (siz[fx] < siz[fy]) {
+			int tmp = fx;
+			fx = fy;
+			fy = tmp;
+		}
+		father[fy] = fx;
+		siz[fx] += siz[fy];
+		rollback[++opsize][0] = fx;
+		rollback[opsize][1] = fy;
+	}
+
+	public static void undo() {
+		int fx = rollback[opsize][0];
+		int fy = rollback[opsize--][1];
+		father[fy] = fy;
+		siz[fx] -= siz[fy];
+	}
+
+	public static void add(int jobl, int jobr, int jobv, int l, int r, int i) {
+		if (jobl <= l && r <= jobr) {
+			addEdgeS(i, jobv);
+		} else {
+			int mid = (l + r) >> 1;
+			if (jobl <= mid) {
+				add(jobl, jobr, jobv, l, mid, i << 1);
+			}
+			if (jobr > mid) {
+				add(jobl, jobr, jobv, mid + 1, r, i << 1 | 1);
+			}
+		}
+	}
+
+	public static void dfs(int l, int r, int i) {
+		int unionCnt = 0;
+		for (int ei = heads[i], fx, fy; ei > 0; ei = nexts[ei]) {
+			fx = find(x[tos[ei]]);
+			fy = find(y[tos[ei]]);
+			if (fx != fy) {
+				union(fx, fy);
+				unionCnt++;
+			}
+		}
+		if (l == r) {
+			for (int ei = headc[l], fx, fy; ei > 0; ei = nextc[ei]) {
+				fx = find(x[toc[ei]]);
+				fy = find(y[toc[ei]]);
+				ans += (long) siz[fx] * siz[fy];
+			}
+		} else {
+			int mid = (l + r) >> 1;
+			dfs(l, mid, i << 1);
+			dfs(mid + 1, r, i << 1 | 1);
+		}
+		for (int k = 1; k <= unionCnt; k++) {
+			undo();
+		}
+	}
+
+	public static void main(String[] args) {
+		FastIO io = new FastIO(System.in, System.out);
+		n = io.nextInt();
+		for (int i = 1; i < n; i++) {
+			x[i] = io.nextInt();
+			y[i] = io.nextInt();
+			c[i] = io.nextInt();
+		}
+		for (int i = 1; i < n; i++) {
+			addEdgeC(c[i], i);
+			if (c[i] > 1) {
+				add(1, c[i] - 1, i, 1, n, 1);
+			}
+			if (c[i] < n) {
+				add(c[i] + 1, n, i, 1, n, 1);
+			}
+		}
+		for (int i = 1; i <= n; i++) {
+			father[i] = i;
+			siz[i] = 1;
+		}
+		dfs(1, n, 1);
+		io.writelnLong(ans);
+		io.flush();
+	}
+
+	// 读写工具类
+	static class FastIO {
+		private final InputStream is;
+		private final OutputStream os;
+		private final byte[] inbuf = new byte[1 << 16];
+		private int lenbuf = 0;
+		private int ptrbuf = 0;
+		private final StringBuilder outBuf = new StringBuilder();
+
+		public FastIO(InputStream is, OutputStream os) {
+			this.is = is;
+			this.os = os;
+		}
+
+		private int readByte() {
+			if (ptrbuf >= lenbuf) {
+				ptrbuf = 0;
+				try {
+					lenbuf = is.read(inbuf);
+				} catch (IOException e) {
+					throw new RuntimeException(e);
+				}
+				if (lenbuf == -1) {
+					return -1;
+				}
+			}
+			return inbuf[ptrbuf++] & 0xff;
+		}
+
+		private int skip() {
+			int b;
+			while ((b = readByte()) != -1) {
+				if (b > ' ') {
+					return b;
+				}
+			}
+			return -1;
+		}
+
+		public int nextInt() {
+			int b = skip();
+			if (b == -1) {
+				throw new RuntimeException("No more integers (EOF)");
+			}
+			boolean negative = false;
+			if (b == '-') {
+				negative = true;
+				b = readByte();
+			}
+			int val = 0;
+			while (b >= '0' && b <= '9') {
+				val = val * 10 + (b - '0');
+				b = readByte();
+			}
+			return negative ? -val : val;
+		}
+
+		public void writelnLong(long x) {
+			outBuf.append(x).append('\n');
+		}
+
+		public void flush() {
+			try {
+				os.write(outBuf.toString().getBytes());
+				os.flush();
+				outBuf.setLength(0);
+			} catch (IOException e) {
+				throw new RuntimeException(e);
+			}
+		}
+	}
+
+}