Initial data commit

Task/Pythagorean-quadruples/Modula-2/pythagorean-quadruples.mod2

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+MODULE PythagoreanQuadruples;
+FROM FormatString IMPORT FormatString;
+FROM RealMath IMPORT sqrt;
+FROM Terminal IMPORT WriteString,WriteLn,ReadChar;
+
+PROCEDURE WriteInteger(i : INTEGER);
+VAR buffer : ARRAY[0..16] OF CHAR;
+BEGIN
+    FormatString("%i", buffer, i);
+    WriteString(buffer)
+END WriteInteger;
+
+(* Main *)
+CONST N = 2200;
+VAR
+    r : ARRAY[0..N] OF BOOLEAN;
+    a,b,c,d : INTEGER;
+    aabb,aabbcc : INTEGER;
+BEGIN
+    (* Initialize *)
+    FOR a:=0 TO HIGH(r) DO
+        r[a] := FALSE
+    END;
+
+    (* Process *)
+    FOR a:=1 TO N DO
+        FOR b:=a TO N DO
+            IF (a MOD 2 = 1) AND (b MOD 2 = 1) THEN
+                (* For positive odd a and b, no solution *)
+                CONTINUE
+            END;
+            aabb := a*a + b*b;
+            FOR c:=b TO N DO
+                aabbcc := aabb + c*c;
+                d := INT(sqrt(FLOAT(aabbcc)));
+                IF (aabbcc = d*d) AND (d <= N) THEN
+                    (* solution *)
+                    r[d] := TRUE
+                END
+            END
+        END
+    END;
+
+    FOR a:=1 TO N DO
+        IF NOT r[a] THEN
+            (* pritn non-solution *)
+            WriteInteger(a);
+            WriteString(" ")
+        END
+    END;
+    WriteLn;
+
+    ReadChar
+END PythagoreanQuadruples.