diff --git a/500 to 1000 difficulty rating/639_Police_and_Thief.cpp b/500 to 1000 difficulty rating/639_Police_and_Thief.cpp
new file mode 100644
index 0000000..92e56e7
--- /dev/null
+++ b/500 to 1000 difficulty rating/639_Police_and_Thief.cpp	
@@ -0,0 +1,23 @@
+// https://www.codechef.com/practice/course/logical-problems/DIFF800/problems/POLTHIEF?tab=statement
+#include <bits/stdc++.h>
+using namespace std;
+
+int main() {
+	// your code goes here
+	int t;
+	cin >> t;
+	while(t--)
+	{
+	    int x, y;
+	    cin >> x >> y;
+	    if(x == y || x > y)
+	    {
+	        cout << x - y << endl;
+	    }
+	    else 
+	    {
+	        cout << y - x << endl;
+	    }
+	}
+
+}