// unsigned integer means positive whole number or 0 uint naturalNumber = 23; // integer means negative or positive whole number or 0 int integerNumber = -23; // float means single-precision floating point // F suffix makes it a float literal float realNumber = 2.3F; // double means double-precision floating point double anotherRealNumber = 2.3; // double literal // three variables that store the number 2 million int decimalNotation = 2_000_000; int binaryNotation = 0b_0001_1110_1000_0100_1000_0000; int hexadecimalNotation = 0x_001E_8480; // check the three variables have the same value // both statements output true Console.WriteLine($"{decimalNotation == binaryNotation}"); Console.WriteLine( $"{decimalNotation == hexadecimalNotation}"); Console.WriteLine($"int uses {sizeof(int)} bytes and can store numbers in the range {int.MinValue:N0} to {int.MaxValue:N0}."); Console.WriteLine($"double uses {sizeof(double)} bytes and can store numbers in the range {double.MinValue:N0} to {double.MaxValue:N0}."); Console.WriteLine($"decimal uses {sizeof(decimal)} bytes and can store numbers in the range {decimal.MinValue:N0} to {decimal.MaxValue:N0}."); Console.WriteLine("Using doubles:"); double a = 0.1; double b = 0.2; if (a + b == 0.3) { Console.WriteLine($"{a} + {b} equals {0.3}"); } else { Console.WriteLine($"{a} + {b} does NOT equal {0.3}"); } Console.WriteLine("Using decimals:"); decimal c = 0.1M; // M suffix means a decimal literal value decimal d = 0.2M; if (c + d == 0.3M) { Console.WriteLine($"{c} + {d} equals {0.3M}"); } else { Console.WriteLine($"{c} + {d} does NOT equal {0.3M}"); }