Submission #890887
Source Code Expand
import java.io.IOException; import java.io.InputStream; import java.io.PrintWriter; import java.util.InputMismatchException; import java.util.NoSuchElementException; public class Main { public static void main(String[] args) { IO io = new IO(); int n = io.nextInt(); int[] a = new int[n]; for(int i=0;i<n;i++) a[i] = io.nextInt() - 1; int sum = 0; for(int i=0;i<n;i++) { if (a[a[i]] == i) { sum++; } } System.out.println(sum / 2); } } class IO extends PrintWriter { private final InputStream in; private final byte[] buffer = new byte[1024]; private int ptr = 0; private int buflen = 0; public IO() { this(System.in);} public IO(InputStream source) { super(System.out); this.in = source;} private boolean hasNextByte() { if (ptr < buflen) { return true; }else{ ptr = 0; try { buflen = in.read(buffer); } catch (IOException e) { e.printStackTrace(); } if (buflen <= 0) { return false; } } return true; } private int readByte() { if (hasNextByte()) return buffer[ptr++]; else return -1;} private static boolean isPrintableChar(int c) { return 33 <= c && c <= 126;} private static boolean isNewLine(int c) { return c == '\n' || c == '\r';} public boolean hasNext() { while(hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; return hasNextByte();} public boolean hasNextLine() { while(hasNextByte() && isNewLine(buffer[ptr])) ptr++; return hasNextByte();} public String next() { if (!hasNext()) { throw new NoSuchElementException(); } StringBuilder sb = new StringBuilder(); int b = readByte(); while(isPrintableChar(b)) { sb.appendCodePoint(b); b = readByte(); } return sb.toString(); } public char[] nextCharArray(int len) { if (!hasNext()) { throw new NoSuchElementException(); } char[] s = new char[len]; int i = 0; int b = readByte(); while(isPrintableChar(b)) { if (i == len) { throw new InputMismatchException(); } s[i++] = (char) b; b = readByte(); } return s; } public String nextLine() { if (!hasNextLine()) { throw new NoSuchElementException(); } StringBuilder sb = new StringBuilder(); int b = readByte(); while(!isNewLine(b)) { sb.appendCodePoint(b); b = readByte(); } return sb.toString(); } public long nextLong() { if (!hasNext()) { throw new NoSuchElementException(); } long n = 0; boolean minus = false; int b = readByte(); if (b == '-') { minus = true; b = readByte(); } if (b < '0' || '9' < b) { throw new NumberFormatException(); } while(true){ if ('0' <= b && b <= '9') { n *= 10; n += b - '0'; }else if(b == -1 || !isPrintableChar(b)){ return minus ? -n : n; }else{ throw new NumberFormatException(); } b = readByte(); } } public int nextInt() { long nl = nextLong(); if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) { throw new NumberFormatException(); } return (int) nl; } public char nextChar() { if (!hasNext()) { throw new NoSuchElementException(); } return (char) readByte(); } public double nextDouble() { return Double.parseDouble(next());} public int[] nextIntArray(int n) { int[] a = new int[n]; for(int i=0;i<n;i++) a[i] = nextInt(); return a;} public long[] nextLongArray(int n) { long[] a = new long[n]; for(int i=0;i<n;i++) a[i] = nextLong(); return a;} public double[] nextDoubleArray(int n) { double[] a = new double[n]; for(int i=0;i<n;i++) a[i] = nextDouble(); return a;} public void nextIntArrays(int[]... a) { for(int i=0;i<a[0].length;i++) for(int j=0;j<a.length;j++) a[j][i] = nextInt();} public int[][] nextIntMatrix(int n,int m) { int[][] a = new int[n][]; for(int i=0;i<n;i++) a[i] = nextIntArray(m); return a;} public char[][] nextCharMap(int n,int m) { char[][] a = new char[n][]; for(int i=0;i<n;i++) a[i] = nextCharArray(m); return a;} public void close() { super.close(); try {in.close();} catch (IOException e) {}} }
Submission Info
Submission Time | |
---|---|
Task | B - Friendly Rabbits |
User | piroz95 |
Language | Java8 (OpenJDK 1.8.0) |
Score | 200 |
Code Size | 4094 Byte |
Status | AC |
Exec Time | 132 ms |
Memory | 9900 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 | 96 ms | 8148 KB |
0_01.txt | AC | 95 ms | 8148 KB |
0_02.txt | AC | 94 ms | 8148 KB |
1_00.txt | AC | 95 ms | 8148 KB |
1_01.txt | AC | 128 ms | 9672 KB |
1_02.txt | AC | 131 ms | 9612 KB |
1_03.txt | AC | 129 ms | 9636 KB |
1_04.txt | AC | 129 ms | 9900 KB |
1_05.txt | AC | 125 ms | 9428 KB |
1_06.txt | AC | 132 ms | 9892 KB |
1_07.txt | AC | 126 ms | 9524 KB |
1_08.txt | AC | 125 ms | 9400 KB |
1_09.txt | AC | 128 ms | 9556 KB |
1_10.txt | AC | 129 ms | 9508 KB |
1_11.txt | AC | 109 ms | 8528 KB |