补充md

8.10/I-Wall/Readme.md

@@ -22,6 +22,20 @@ Next N lines describe coordinates of castle's vertices in a clockwise order. Eac
 
 ### Output
 Write to the output file the single number that represents the minimal possible length of the wall in feet that could be built around the castle to satisfy King's requirements. You must present the integer number of feet to the King, because the floating numbers are not invented yet. However, you must round the result in such a way, that it is accurate to 8 inches (1 foot is equal to 12 inches), since the King will not tolerate larger error in the estimates.
+### Sample
+#### input
+9 100
+200 400
+300 400
+300 300
+400 300
+400 400
+500 400
+500 200
+350 200
+200 200
+#### output
+1628
 ### Hint
 结果四舍五入就可以了