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@PreSoichiSumi
Created April 26, 2016 07:47
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import java.io.IOException;
import java.io.InputStream;
import java.util.*;
public class Main {
private static final double EPS = 1e-10;
public static void main(String args[]) {
FastScanner sc = new FastScanner();
int n = sc.nextInt();
int x[]=new int[n];
int y[]=new int[n];
for(int i=0;i<n;i++){
x[i]=sc.nextInt();
y[i]=sc.nextInt();
}
int tyo=0;
int don=0;
for(int i=0;i<n;i++){
double diglist[]=new double[(n-1)*2];
for(int j=0;j<n;j++){
if(i==j)continue;
diglist[j<i?j:j-1]=Math.atan2(y[j]-y[i],
x[j]-x[i]);
}
for(int j=0;j<n-1;j++){
diglist[n-1+j]=diglist[j]+Math.PI*2;
}
Arrays.sort(diglist);
int pos1=0,pos2=0,pos3=0;
for(int j=0;j<n-1;j++){
while(diglist[pos1]-diglist[j]+EPS
< (Math.PI/2)) pos1++;
while(diglist[pos2]-diglist[j]-EPS
< (Math.PI/2)) pos2++;
while(diglist[pos3]-diglist[j]+EPS
< Math.PI) pos3++;
tyo+= pos2-pos1;
don+= pos3-pos2;
}
}
long ei= (long)n*(n-1)*(n-2)/6 -tyo-don;
System.out.println(ei+" " + tyo+" " +don);
}
}
class FastScanner {
private final InputStream in = System.in;
private final byte[] buffer = new byte[1024];
private int ptr = 0;
private int buflen = 0;
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 boolean isPrintableChar(int c) {
return 33 <= c && c <= 126;
}
private void skipUnprintable() {
while (hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++;
}
public boolean hasNext() {
skipUnprintable();
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 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() {
if (!hasNext()) throw new NoSuchElementException();
int 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();
}
}
}
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