Submission #890897
Source Code Expand
import java.io.OutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.io.PrintWriter; import java.io.BufferedWriter; import java.io.Writer; import java.io.OutputStreamWriter; import java.util.InputMismatchException; import java.io.IOException; import java.io.InputStream; /** * Built using CHelper plug-in * Actual solution is at the top * * @author ilyakor */ public class Main { public static void main(String[] args) { InputStream inputStream = System.in; OutputStream outputStream = System.out; InputReader in = new InputReader(inputStream); OutputWriter out = new OutputWriter(outputStream); TaskB solver = new TaskB(); solver.solve(1, in, out); out.close(); } static class TaskB { public void solve(int testNumber, InputReader in, OutputWriter out) { int n = in.nextInt(); int[] a = new int[n]; for (int i = 0; i < n; ++i) a[i] = in.nextInt() - 1; int res = 0; for (int i = 0; i < n; ++i) if (a[a[i]] == i) ++res; out.printLine(res / 2); } } static class OutputWriter { private final PrintWriter writer; public OutputWriter(OutputStream outputStream) { writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream))); } public OutputWriter(Writer writer) { this.writer = new PrintWriter(writer); } public void print(Object... objects) { for (int i = 0; i < objects.length; i++) { if (i != 0) { writer.print(' '); } writer.print(objects[i]); } } public void printLine(Object... objects) { print(objects); writer.println(); } public void close() { writer.close(); } } static class InputReader { private InputStream stream; private byte[] buffer = new byte[10000]; private int cur; private int count; public InputReader(InputStream stream) { this.stream = stream; } public static boolean isSpace(int c) { return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1; } public int read() { if (count == -1) { throw new InputMismatchException(); } try { if (cur >= count) { cur = 0; count = stream.read(buffer); if (count <= 0) return -1; } } catch (IOException e) { throw new InputMismatchException(); } return buffer[cur++]; } public int readSkipSpace() { int c; do { c = read(); } while (isSpace(c)); return c; } public int nextInt() { int sgn = 1; int c = readSkipSpace(); if (c == '-') { sgn = -1; c = read(); } int res = 0; do { if (c < '0' || c > '9') { throw new InputMismatchException(); } res = res * 10 + c - '0'; c = read(); } while (!isSpace(c)); res *= sgn; return res; } } }
Submission Info
Submission Time | |
---|---|
Task | B - Friendly Rabbits |
User | ilyakor |
Language | Java8 (OpenJDK 1.8.0) |
Score | 200 |
Code Size | 3721 Byte |
Status | AC |
Exec Time | 126 ms |
Memory | 9428 KB |
Judge Result
Set Name | Sample | All | ||||
---|---|---|---|---|---|---|
Score / Max Score | 0 / 0 | 200 / 200 | ||||
Status |
|
|
Set Name | Test Cases |
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Sample | 0_00.txt, 0_01.txt, 0_02.txt |
All | 0_00.txt, 0_01.txt, 0_02.txt, 1_00.txt, 1_01.txt, 1_02.txt, 1_03.txt, 1_04.txt, 1_05.txt, 1_06.txt, 1_07.txt, 1_08.txt, 1_09.txt, 1_10.txt, 1_11.txt |
Case Name | Status | Exec Time | Memory |
---|---|---|---|
0_00.txt | AC | 91 ms | 8404 KB |
0_01.txt | AC | 95 ms | 8404 KB |
0_02.txt | AC | 96 ms | 8404 KB |
1_00.txt | AC | 96 ms | 8276 KB |
1_01.txt | AC | 126 ms | 9172 KB |
1_02.txt | AC | 118 ms | 9300 KB |
1_03.txt | AC | 117 ms | 9300 KB |
1_04.txt | AC | 123 ms | 9428 KB |
1_05.txt | AC | 124 ms | 9300 KB |
1_06.txt | AC | 117 ms | 9172 KB |
1_07.txt | AC | 125 ms | 9300 KB |
1_08.txt | AC | 110 ms | 8916 KB |
1_09.txt | AC | 111 ms | 9172 KB |
1_10.txt | AC | 121 ms | 9168 KB |
1_11.txt | AC | 109 ms | 8788 KB |