"content":"<p>Suppose you are given the following code:</p>\n\n<pre>\nclass FooBar {\n public void foo() {\n for (int i = 0; i < n; i++) {\n print("foo");\n }\n }\n\n public void bar() {\n for (int i = 0; i < n; i++) {\n print("bar");\n }\n }\n}\n</pre>\n\n<p>The same instance of <code>FooBar</code> will be passed to two different threads:</p>\n\n<ul>\n\t<li>thread <code>A</code> will call <code>foo()</code>, while</li>\n\t<li>thread <code>B</code> will call <code>bar()</code>.</li>\n</ul>\n\n<p>Modify the given program to output <code>"foobar"</code> <code>n</code> times.</p>\n\n<p> </p>\n<p><strong class=\"example\">Example 1:</strong></p>\n\n<pre>\n<strong>Input:</strong> n = 1\n<strong>Output:</strong> "foobar"\n<strong>Explanation:</strong> There are two threads being fired asynchronously. One of them calls foo(), while the other calls bar().\n"foobar" is being output 1 time.\n</pre>\n\n<p><strong class=\"example\">Example 2:</strong></p>\n\n<pre>\n<strong>Input:</strong> n = 2\n<strong>Output:</strong> "foobarfoobar"\n<strong>Explanation:</strong> "foobar" is being output 2 times.\n</pre>\n\n<p> </p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li><code>1 <= n <= 1000</code></li>\n</ul>\n",
"similarQuestions":"[{\"title\": \"Print in Order\", \"titleSlug\": \"print-in-order\", \"difficulty\": \"Easy\", \"translatedTitle\": null}, {\"title\": \"Print Zero Even Odd\", \"titleSlug\": \"print-zero-even-odd\", \"difficulty\": \"Medium\", \"translatedTitle\": null}]",
"exampleTestcases":"1\n2",
"categoryTitle":"Concurrency",
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"lang":"C++",
"langSlug":"cpp",
"code":"class FooBar {\nprivate:\n int n;\n\npublic:\n FooBar(int n) {\n this->n = n;\n }\n\n void foo(function<void()> printFoo) {\n \n for (int i = 0; i < n; i++) {\n \n \t// printFoo() outputs \"foo\". Do not change or remove this line.\n \tprintFoo();\n }\n }\n\n void bar(function<void()> printBar) {\n \n for (int i = 0; i < n; i++) {\n \n \t// printBar() outputs \"bar\". Do not change or remove this line.\n \tprintBar();\n }\n }\n};",
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"lang":"Java",
"langSlug":"java",
"code":"class FooBar {\n private int n;\n\n public FooBar(int n) {\n this.n = n;\n }\n\n public void foo(Runnable printFoo) throws InterruptedException {\n \n for (int i = 0; i < n; i++) {\n \n \t// printFoo.run() outputs \"foo\". Do not change or remove this line.\n \tprintFoo.run();\n }\n }\n\n public void bar(Runnable printBar) throws InterruptedException {\n \n for (int i = 0; i < n; i++) {\n \n // printBar.run() outputs \"bar\". Do not change or remove this line.\n \tprintBar.run();\n }\n }\n}",
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"lang":"Python",
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"code":"class FooBar(object):\n def __init__(self, n):\n self.n = n\n\n\n def foo(self, printFoo):\n \"\"\"\n :type printFoo: method\n :rtype: void\n \"\"\"\n for i in xrange(self.n):\n \n # printFoo() outputs \"foo\". Do not change or remove this line.\n \tprintFoo()\n\n\n def bar(self, printBar):\n \"\"\"\n :type printBar: method\n :rtype: void\n \"\"\"\n for i in xrange(self.n):\n \n # printBar() outputs \"bar\". Do not change or remove this line.\n \tprintBar()",
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"lang":"Python3",
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"code":"class FooBar:\n def __init__(self, n):\n self.n = n\n\n\n def foo(self, printFoo: 'Callable[[], None]') -> None:\n \n for i in range(self.n):\n \n # printFoo() outputs \"foo\". Do not change or remove this line.\n \tprintFoo()\n\n\n def bar(self, printBar: 'Callable[[], None]') -> None:\n \n for i in range(self.n):\n \n # printBar() outputs \"bar\". Do not change or remove this line.\n \tprintBar()",
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"lang":"C",
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"code":"typedef struct {\n int n;\n} FooBar;\n\nFooBar* fooBarCreate(int n) {\n FooBar* obj = (FooBar*) malloc(sizeof(FooBar));\n obj->n = n;\n return obj;\n}\n\nvoid foo(FooBar* obj) {\n \n for (int i = 0; i < obj->n; i++) {\n \n // printFoo() outputs \"foo\". Do not change or remove this line.\n printFoo();\n }\n}\n\nvoid bar(FooBar* obj) {\n \n for (int i = 0; i < obj->n; i++) {\n \n // printBar() outputs \"bar\". Do not change or remove this line.\n printBar();\n }\n}\n\nvoid fooBarFree(FooBar* obj) {\n \n}",
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"lang":"C#",
"langSlug":"csharp",
"code":"public class FooBar {\n private int n;\n\n public FooBar(int n) {\n this.n = n;\n }\n\n public void Foo(Action printFoo) {\n \n for (int i = 0; i < n; i++) {\n \n \t// printFoo() outputs \"foo\". Do not change or remove this line.\n \tprintFoo();\n }\n }\n\n public void Bar(Action printBar) {\n \n for (int i = 0; i < n; i++) {\n \n // printBar() outputs \"bar\". Do not change or remove this line.\n \tprintBar();\n }\n }\n}",
"envInfo":"{\"cpp\": [\"C++\", \"<p>Compiled with <code> clang 11 </code> using the latest C++ 20 standard.</p>\\r\\n\\r\\n<p>Your code is compiled with level two optimization (<code>-O2</code>). <a href=\\\"https://github.com/google/sanitizers/wiki/AddressSanitizer\\\" target=\\\"_blank\\\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\\r\\n\\r\\n<p>Most standard library headers are already included automatically for your convenience.</p>\"], \"java\": [\"Java\", \"<p><code>OpenJDK 17</code>. Java 8 features such as lambda expressions and stream API can be used. </p>\\r\\n\\r\\n<p>Most standard library headers are already included automatically for your convenience.</p>\\r\\n<p>Includes <code>Pair</code> class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.</p>\"], \"python\": [\"Python\", \"<p><code>Python 2.7.12</code>.</p>\\r\\n\\r\\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\\\"https://docs.python.org/2/library/array.html\\\" target=\\\"_blank\\\">array</a>, <a href=\\\"https://docs.python.org/2/library/bisect.html\\\" target=\\\"_blank\\\">bisect</a>, <a href=\\\"https://docs.python.org/2/library/collections.html\\\" target=\\\"_blank\\\">collections</a>. If you need more libraries, you can import it yourself.</p>\\r\\n\\r\\n<p>For Map/TreeMap data structure, you may use <a href=\\\"http://www.grantjenks.com/docs/sortedcontainers/\\\" target=\\\"_blank\\\">sortedcontainers</a> library.</p>\\r\\n\\r\\n<p>Note that Python 2.7 <a href=\\\"https://www.python.org/dev/peps/pep-0373/\\\" target=\\\"_blank\\\">will not be maintained past 2020</a>. For the latest Python, please choose Python3 instead.</p>\"], \"c\": [\"C\", \"<p>Compiled with <code>gcc 8.2</code> using the gnu11 standard.</p>\\r\\n\\r\\n<p>Your code is compiled with level one optimization (<code>-O1</code>). <a href=\\\"https://github.com/google/sanitizers/wiki/AddressSanitizer\\\" target=\\\"_blank\\\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\\r\\n\\r\\n<p>Most standard library headers are already included automatically for your convenience.</p>\\r\\n\\r\\n<p>For hash table operations, you may use <a href=\\\"https://troydhanson.github.io/uthash/\\\" target=\\\"_blank\\\">uthash</a>. \\\"uthash.h\\\" is included by default. Below are some examples:</p>\\r\\n\\r\\n<p><b>1. Adding an item to a hash.</b>\\r\\n<pre>\\r\\nstruct hash_entry {\\r\\n int id; /* we'll use this field as the key */\\r\\n char name[10];\\r\\n UT_hash_handle hh; /* makes this structure hashable */\\r\\n};\\r\\n\\r\\nstruct hash_entry *users = NULL;\\r\\n\\r\\nvoid add_user(struct hash_entry *s) {\\r\\n HASH_ADD_INT(users, id, s);\\r\\n}\\r\\n</pre>\\r\\n</p>\\r\\n\\r\\n<p><b>2. Looking up an item in a hash:</b>\\r\\n<pre>\\r\\nstruct hash_entry *find_user(int user_id) {\\r\\n struct hash_entry *s;\\r\\n HASH_FIND_INT(users, &user_id, s);\\r\\n return s;\\r\\n}\\r\\n</pre>\\r\\n</p>\\r\\n\\r\\n<p><b>3. Deleting an item in a hash:</b>\\r\\n<pre>\\r\\nvoid delete_user(struct hash_entry *user) {\\r\\n HASH_DEL(users, user); \\r\\n}\\r\\n</pre>\\r\\n</p>\"], \"csharp\": [\"C#\", \"<p><a href=\\\"https://learn.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-10\\\" target=\\\"_blank\\\">C# 10 with .NET 6 runtime</a></p>\"], \"python3\": [\"Python3\", \"<p><code>Python 3.10</code>.</p>\\r\\n\\r\\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\\\"https://docs.python.org/3/library/array.html\\\" target=\\\"_blank\\\">array</a>, <a href=\\\"https://docs.python.org/3/library/bisect.html\\\" target=\\\"_blank\\\">bisect</a>, <a href=\\\"https://docs.python.org/3/library/collections.html\\\" target=\\\"_blank\\\">collections</a>. If you need more libraries, you can import it yourself.</p>\\r\\n\\r\\n<p>For Map/TreeMap data structure, you may use <a href=\\\"http://www.grantjenks.com/docs/sortedcontainers/\\\" target=\\\"_blank\\\"
