March 2014 update

Task/Modular-inverse/00DESCRIPTION

@@ -2,7 +2,7 @@ From [http://en.wikipedia.org/wiki/Modular_multiplicative_inverse Wikipedia]:
 
 :In [[wp:modular arithmetic|modular arithmetic]], the '''modular multiplicative inverse''' of an [[integer]] ''a'' [[wp:modular arithmetic|modulo]] ''m'' is an integer ''x'' such that
 
-::<math>a^{-1} \equiv x \pmod{m}.</math>
+::<math>a\,x \equiv 1 \pmod{m}.</math>
 
 Or in other words, such that:
 :<math>\exists k \in\mathbf{Z},\qquad a\, x = 1 + k\,m</math>

Task/Modular-inverse/AutoHotkey/modular-inverse.ahk

@@ -0,0 +1,19 @@
+MsgBox, % ModInv(42, 2017)
+
+ModInv(a, b) {
+	if (b = 1)
+		return 1
+	b0 := b, x0 := 0, x1 :=1
+	while (a > 1) {
+		q := a // b
+		, t  := b
+		, b  := Mod(a, b)
+		, a  := t
+		, t  := x0
+		, x0 := x1 - q * x0
+		, x1 := t
+	}
+	if (x1 < 0)
+		x1 += b0
+	return x1
+}

Task/Modular-inverse/C/modular-inverse.c

@@ -1,20 +1,18 @@
-#include <stdio.h>
-
-int mul_inv(int a, int b)
-{
-	int b0 = b, t, q;
-	int x0 = 0, x1 = 1;
-	if (b == 1) return 1;
-	while (a > 1) {
-		q = a / b;
-		t = b, b = a % b, a = t;
-		t = x0, x0 = x1 - q * x0, x1 = t;
-	}
-	if (x1 < 0) x1 += b0;
-	return x1;
+#include<stdio.h>
+int modularinverse( int a, int b){
+	int c=b/a,x=0;
+	do{
+		if((a<b)||(a==1)) x=1;
+		if((c*a)%b==1) x=c;
+		else c++;
+	} while(x==0);
+	return x;
 }
-
-int main(void) {
-	printf("%d\n", mul_inv(42, 2017));
+int main()
+{
+	int a,b;
+	printf("Unesite brojeve a i b ");
+	scanf("%d%d",&a,&b);
+	printf("Modularni inverz brojeva %d i %d je %d ",a,b,modularinverse(a,b));
 	return 0;
 }

Task/Modular-inverse/Maple/modular-inverse.maple

@@ -0,0 +1 @@
+1/42 mod 2017;

Task/Modular-inverse/Perl-6/modular-inverse.pl6

@@ -5,7 +5,7 @@ sub inverse($n, :$modulo) {
         ($q, $c, $d) = ($d div $c, $d % $c, $c);
         ($uc, $vc, $ud, $vd) = ($ud - $q*$uc, $vd - $q*$vc, $uc, $vc);
     }
-    return $ud < 0 ?? $ud + $modulo !! $ud;
+    return $ud % $modulo;
 }
 
 say inverse 42, :modulo(2017)