{"trustable":true,"sections":[{"title":"","value":{"format":"HTML","content":"Given n, a positive integer, how many positive integers less than n are relatively prime to n? Two integers a and b are relatively prime if there are no integers x \u0026gt; 1, y \u0026gt; 0, z \u0026gt; 0 such that a \u003d xy and b \u003d xz. "}},{"title":"Input","value":{"format":"HTML","content":"There are several test cases. For each test case, standard input contains a line with n \u0026lt;\u003d 1,000,000,000. A line containing 0 follows the last case. "}},{"title":"Output","value":{"format":"HTML","content":"For each test case there should be single line of output answering the question posed above."}},{"title":"Sample","value":{"format":"HTML","content":"\u003ctable class\u003d\u0027vjudge_sample\u0027\u003e\n\u003cthead\u003e\n \u003ctr\u003e\n \u003cth\u003eInput\u003c/th\u003e\n \u003cth\u003eOutput\u003c/th\u003e\n \u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\u003cpre\u003e7\r\n12\r\n0\r\n\u003c/pre\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cpre\u003e6\r\n4\r\n\u003c/pre\u003e\u003c/td\u003e\n \u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n"}}]}