private int Min(int a, int b, int c) => Math.Min(a, Math.Min(b, c));
private char Min(char a, char b, char c) {
a = a < b ? a : b;
a = a < c ? a : c;
return a;
}
private double Min(double a, double b, double c, double d) => Math.Min(a, Math.Min(b, Math.Min(c, d)));