Data commit

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

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+// The Kotlin compiler can detect expressions of signed constant integers that will overflow.
+// It cannot detect unsigned integer overflow, however.
+@Suppress("INTEGER_OVERFLOW")
+fun main() {
+    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)
+    println("\n*** Unsigned 32 bit integers ***\n")
+//    println(-4294967295U) // this is a compiler error since unsigned integers have no negation operator
+//    println(0U - 4294967295U) // this works
+    println((-4294967295).toUInt()) // converting from the signed Int type also produces the overflow; this is intended behavior of toUInt()
+    println(3000000000U + 3000000000U)
+    println(2147483647U - 4294967295U)
+    println(65537U * 65537U)
+    println("\n*** Unsigned 64 bit integers ***\n")
+    println(0U - 18446744073709551615U) // we cannot convert from a signed type here (since none big enough exists) and have to use subtraction
+    println(10000000000000000000U + 10000000000000000000U)
+    println(9223372036854775807U - 18446744073709551615U)
+    println(4294967296U * 4294967296U)
+}