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leetcode/problem/print-foobar-alternately.html

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+<p>Suppose you are given the following code:</p>
+
+<pre>
+class FooBar {
+  public void foo() {
+    for (int i = 0; i &lt; n; i++) {
+      print(&quot;foo&quot;);
+    }
+  }
+
+  public void bar() {
+    for (int i = 0; i &lt; n; i++) {
+      print(&quot;bar&quot;);
+    }
+  }
+}
+</pre>
+
+<p>The same instance of <code>FooBar</code> will be passed to two different threads:</p>
+
+<ul>
+	<li>thread <code>A</code> will call <code>foo()</code>, while</li>
+	<li>thread <code>B</code> will call <code>bar()</code>.</li>
+</ul>
+
+<p>Modify the given program to output <code>&quot;foobar&quot;</code> <code>n</code> times.</p>
+
+<p>&nbsp;</p>
+<p><strong>Example 1:</strong></p>
+
+<pre>
+<strong>Input:</strong> n = 1
+<strong>Output:</strong> &quot;foobar&quot;
+<strong>Explanation:</strong> There are two threads being fired asynchronously. One of them calls foo(), while the other calls bar().
+&quot;foobar&quot; is being output 1 time.
+</pre>
+
+<p><strong>Example 2:</strong></p>
+
+<pre>
+<strong>Input:</strong> n = 2
+<strong>Output:</strong> &quot;foobarfoobar&quot;
+<strong>Explanation:</strong> &quot;foobar&quot; is being output 2 times.
+</pre>
+
+<p>&nbsp;</p>
+<p><strong>Constraints:</strong></p>
+
+<ul>
+	<li><code>1 &lt;= n &lt;= 1000</code></li>
+</ul>