From 00d8d550b5037d44385b2ccd35d543da5aa087ed Mon Sep 17 00:00:00 2001
From: Xuanyu Chen <xuychen@ucdavis.edu>
Date: Tue, 17 Oct 2017 10:47:40 -0700
Subject: [PATCH] Add files via upload

drop rows, not yet
---
 P.R | 55 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 55 insertions(+)
 create mode 100644 P.R

diff --git a/P.R b/P.R
new file mode 100644
index 0000000..54666d6
--- /dev/null
+++ b/P.R
@@ -0,0 +1,55 @@
+library(data.table)
+library(parallel)
+nthread = 4
+count = 0
+cluster = makePSOCKcluster(rep("localhost", nthread))
+data = fread("test1.txt", sep = " ", header = FALSE)
+
+smaller_than <- function(lhs, rhs) {
+	#both are pair
+	if (lhs[1] == rhs[1])
+		return (lhs[2] < rhs[2])
+	else
+		return (lhs[1] < rhs[1])
+}
+
+binary_search <- function (edges, value) {
+	up = nrow(edges)
+	down = 1
+	
+	while(down <= up) {
+		midpoint = ceiling((up+down)/2)
+		pair = as.numeric(edges[midpoint])
+		if (smaller_than(value, pair))
+			up = midpoint - 1
+		else if (smaller_than(pair, value))
+			down = midpoint + 1
+		else
+			return (midpoint)
+	}
+	
+	return (-1)
+}
+
+recippar <- function (edges) {
+	data = edges[order(V1, V2),]
+	for(x in 1:nrow(data))
+		found <- binary_search(data, as.numeric(data[x]))
+		if(found != -1) {
+			if(found > x) {
+				data = data[-found,]
+				data = data[-x,]
+			}
+			else {
+				data = data[-x,]
+				data = data[-found,]
+			}
+			count = count + 1
+		}
+		else
+			data = data[-x,]
+			
+  count / 2
+}
+
+recippar(data)