Update README.md

HEXOGEN616 · HEXOGEN616 · commit 30dce929eacb · 2018-12-18T13:20:32.000+08:00
diff --git a/README.md b/README.md
@@ -1 +1,2 @@
 # PR test
+I need a program to display "Hello world".

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`@@ -1 +1,2 @@`
`1`	`1`	`# PR test`
	`2`	`+I need a program to display "Hello world".`