teamnote history merge

2024fall/source/Math/Diophantos.cpp

@@ -0,0 +1,14 @@
+pll diophantos(ll a, ll b)
+{
+    assert(a>0 and b>=0);
+    if(b == 0) return {1, 0};
+    auto [y, x] = diophantos(b, a%b); y = y-(a/b)*x;
+    if(x < 0 or x >= b)
+    {
+        ll t = x/b;
+        if(x%b < 0) t--;
+
+        x -= b*t; y += a*t;
+    }
+    return {x, y};
+}