{"raw_statement":[{"iden":"problem statement","content":"A function $f(x)$ defined for non-negative integer $x$ satisfies the following conditions:\n\n*   $f(0) = 1$;\n*   $f(k) = k \\times f(k-1)$ for all positive integers $k$.\n\nFind $f(N)$."},{"iden":"constraints","content":"*   $N$ is an integer such that $0 \\le N \\le 10$."},{"iden":"input","content":"The input is given from Standard Input in the following format:\n\n$N$"},{"iden":"sample input 1","content":"2"},{"iden":"sample output 1","content":"2\n\nWe have $f(2) = 2 \\times f(1) = 2 \\times 1 \\times f(0) = 2 \\times 1 \\times 1 = 2$."},{"iden":"sample input 2","content":"3"},{"iden":"sample output 2","content":"6\n\nWe have $f(3) = 3 \\times f(2) = 3 \\times 2 = 6$."},{"iden":"sample input 3","content":"0"},{"iden":"sample output 3","content":"1"},{"iden":"sample input 4","content":"10"},{"iden":"sample output 4","content":"3628800"}],"translated_statement":null,"sample_group":[],"show_order":["default"],"formal_statement":null,"simple_statement":null,"has_page_source":true}