September 2017 Update

Task/Integer-overflow/Kotlin/integer-overflow.kotlin

@@ -0,0 +1,29 @@
+// version 1.0.5-2
+
+/*  Kotlin (like Java) does not have unsigned integer types but we can simulate
+    what would happen if we did have an unsigned 32 bit integer type using this extension function */
+fun Long.toUInt(): Long = this and 0xffffffffL
+
+@Suppress("INTEGER_OVERFLOW")
+fun main(args: Array<String>) {
+    // The following 'signed' computations all produce compiler warnings that they will lead to an overflow
+    // which have been ignored
+    println("*** Signed 32 bit integers ***\n")
+    println(-(-2147483647 - 1))
+    println(2000000000 + 2000000000)
+    println(-2147483647 - 2147483647)
+    println(46341 * 46341)
+    println((-2147483647 - 1) / -1)
+    println("\n*** Signed 64 bit integers ***\n")
+    println(-(-9223372036854775807 - 1))
+    println(5000000000000000000 + 5000000000000000000)
+    println(-9223372036854775807 - 9223372036854775807)
+    println(3037000500 * 3037000500)
+    println((-9223372036854775807 - 1) / -1)
+    // Simulated unsigned computations, no overflow warnings as we're using the Long type
+    println("\n*** Unsigned 32 bit integers ***\n")
+    println((-4294967295L).toUInt())
+    println((3000000000L.toUInt() + 3000000000L.toUInt()).toUInt())
+    println((2147483647L - 4294967295L.toUInt()).toUInt())
+    println((65537L * 65537L).toUInt())
+}