variadic MathLib.gcd

NASU41 · NASU41 · commit 870991aefd30 · 2021-06-09T16:17:38.000+09:00
diff --git a/Math/MathLib.java b/Math/MathLib.java
@@ -22,16 +22,27 @@ private static long[] inv_gcd(long a, long b){
         return new long[]{s,m0};
     }
 
-    public static long gcd(long a, long b){
-        a = java.lang.Math.abs(a);
-        b = java.lang.Math.abs(b);
-        return inv_gcd(a, b)[0];       
+    public static long gcd(long... a){
+        if(a.length == 0) return 0;
+        long r = java.lang.Math.abs(a[0]);
+        for(int i=1; i<a.length; i++){
+            r = inv_gcd(r, java.lang.Math.abs(a[i]))[0];
+        }
+        return r;
     }
     public static long lcm(long a, long b){
         a = java.lang.Math.abs(a);
         b = java.lang.Math.abs(b);
         return a / gcd(a,b) * b;
     }
+    public static long lcm(long... a){
+        if(a.length == 0) return 0;
+        long r = java.lang.Math.abs(a[0]);
+        for(int i=1; i<a.length; i++){
+            r = r / gcd(r,java.lang.Math.abs(a[i])) * java.lang.Math.abs(a[i]);
+        }
+        return r;
+    }
 
     public static long pow_mod(long x, long n, int m){
         assert n >= 0;
