Data commit

Task/Totient-function/XPL0/totient-function.xpl0

@@ -0,0 +1,42 @@
+func GCD(N, D);         \Return the greatest common divisor of N and D
+int  N, D;              \numerator and denominator
+int  R;
+[if D > N then
+    [R:= D;  D:= N;  N:= R];    \swap D and N
+while D > 0 do
+    [R:= rem(N/D);
+    N:= D;
+    D:= R;
+    ];
+return N;
+];      \GCD
+
+func Totient(N);        \Return the totient of N
+int  N, Phi, M;
+[Phi:= 0;
+for M:= 1 to N do
+    if GCD(M, N) = 1 then Phi:= Phi+1;
+return Phi;
+];
+
+int N, Phi, Pwr, C, Limit;
+[Text(0, "n       phi     is prime^m^j");
+for N:= 1 to 25 do
+    [IntOut(0, N);  ChOut(0, 9\tab\);
+    Phi:= Totient(N);
+    IntOut(0, Phi);  ChOut(0, 9\tab\);
+    Text(0, if Phi = N-1 then "true" else "false");
+    CrLf(0);
+    ];
+CrLf(0);
+for Pwr:= 2 to 4 do
+    [C:= 0;
+    Limit:= fix(Pow(10.0, float(Pwr)));
+    IntOut(0, Limit);  ChOut(0, 9\tab\);
+    for N:= 1 to Limit do
+        [Phi:= Totient(N);
+        if Phi = N-1 then C:= C+1;
+        ];
+    IntOut(0, C);  CrLf(0);
+    ];
+]