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;LIBHDR GCD(P,Q) Q?GCD(Q,P#Q),P TEST(P,Q,R) WRITEF("GCD(%I4,%I4)=%I4 [%I4]*N",P,Q,GCD(P,Q),R) MAIN() [ TEST(4,16,4); TEST(16,4,4); TEST(15,60,15); TEST(15,65,5); TEST(1052,52,4); 0 ]