Update README.md

Light-City · web-flow · commit ffa2f33886f3 · 2021-04-03T17:27:34.000+08:00
diff --git a/design_pattern/singleton/README.md b/design_pattern/singleton/README.md
@@ -185,7 +185,7 @@ singleton *instance() {
         lock_guard<mutex> guard(lock_);
         if (p == nullptr) {
             singleton *tmp = static_cast<singleton *>(operator new(sizeof(singleton)));
-            new(p)singleton();
+            new(tmp)singleton();
             p = tmp;
         }
     }

Original file line number	Diff line number	Diff line change
`@@ -185,7 +185,7 @@ singleton *instance() {`
`185`	`185`	`lock_guard<mutex> guard(lock_);`
`186`	`186`	`if (p == nullptr) {`
`187`	`187`	`singleton tmp = static_cast<singleton >(operator new(sizeof(singleton)));`
`188`		`- new(p)singleton();`
	`188`	`+ new(tmp)singleton();`
`189`	`189`	`p = tmp;`
`190`	`190`	`}`
`191`	`191`	`}`