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"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>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>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",
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"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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"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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"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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"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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"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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