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Questions tagged [integer-overflow]

Integer overflow occurs when the result of an operation is larger than the maximal value that can be represented by the underlying integer type.

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C++ long overflowing prematurely

I'm having a bizarre problem with C++ where the long data type is overflowing long before it should. What I'm doing (with success so far) is to have integers behave like floats, so that the range [-32767,32767] is mapped to [-1.0,1.0]. Where it…
rhodri
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Does modulus overflow?

I know that (INT_MIN / -1) overflows, but (INT_MIN % -1) does not. At least this is what happens in two compilers, one pre-c++11 (VC++ 2010) and the other post-c++11 GCC 4.8.1 int x = INT_MIN; cout << x / -1 << endl; cout << x % -1 <<…
Red
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Catch integer exceptions in Fortran

Is there a way to catch integer exceptions with gfortran or ifort like there is for catching floating point exceptions? Consider this simple program to calculate the factorial: program factorial use, intrinsic :: iso_fortran_env implicit…
Alexander Vogt
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Why do integer datatypes overflow silently rather than throwing exception

I have learnt(atleast in java) that integer/long values overflow silently and their values start over from minimum value on overflow rather than throwing any exception. I was using an external api for some file operations, in which max file size was…
Aqeel Ashiq
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How to suppress overflow-checking in PowerShell?

PowerShell seems to perform bounds-checking after arithmetic operations and conversions. For instance, the following operations fail: [byte]$a = 255 $a++ $a = [byte]256 Is there any way to enforce overflows or the typecast without resorting to a…
Chrysler
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32bit int * 32bit int = 64 bit int?

In other words does this work as expected? int32 i = INT_MAX-1; int64 j = i * i; or do I need to cast the i to 64 bit first?
Michael
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Is there any difference between overflow and implicit conversion, whether technical or bit level (cpu-register-level)?

(I'm an novice, so there may be inaccuracies in what I say) In my current mental model, an overflow is an arithmetical phenomenon (occurs when we perform arithmetic operations), and an implicit conversion is an assignment (initialization or not)…
Manuel
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Generally, How do I prevent integer overflow from happening in C language?

Generally, How can I prevent integer overflow from happening in C programming language? I mean, Is there any functions to prevent? And finally, Is integer overflow going to get me hacked like buffer overflow or etc?
Amir Mohsen Ghasemi
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Is the size of an array constrained by the upper limit of int (2147483647)?

I'm doing some Project Euler exercises and I've run into a scenario where I have want arrays which are larger than 2,147,483,647 (the upper limit of int in C#). Sure these are large arrays, but for instance, I can't do this // fails bool[]…
Ian G
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PANDAS: int32 overflow? Can't bulid a pivot table

I use the pd.pivot_table() method to create a user-item matrix by pivoting the user-item activity data. However, the dataframe is so large that I got complain like this: Unstacked DataFrame is too big, causing int32 overflow Any suggestions on…
JoFox
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Why does C# issue the error "cannot implicitly convert int to ushort" against modulo arithmetic on ushorts?

In another thread, someone asked about why adding two ushort values raised errors in C#. e.g. ushort x = 4; ushort y = 23; ushort z = x+y; // ERROR cannot implicitly convert int to ushort On that thread, people argued that the plus + operater…
Gregory Fenn
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Modular inverses and unsigned integers

Modular inverses can be computed as follows (from Rosetta Code): #include int mul_inv(int a, int b) { int b0 = b, t, q; int x0 = 0, x1 = 1; if (b == 1) return 1; while (a > 1) { q = a / b; t = b, b = a %…
Ecir Hana
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How to store long in a Swift array?

I got a couple user IDs I want to send in an array, but can't figure out the correct Swift 3 syntax for creating an array with very long integers. I tried casting, @ prefix and using as AnyObject, but that did not work. let idArray =…
Alex Stone
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Is over/underflow an undefined behavior at execution time?

I was reading about undefined behavior, and I'm not sure if it's a compile-time only feature, or if it can occurs at execution-time. I understand this example well (this is extracted from the Undefined Behavior page of Wikipedia): An example for…
Jules Lamur
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Signed integer overflow: 999999999 * 10 cannot be represented in type 'int' Error

Why is there a runtime error? I made range2 a long long. Code: /*VARIABLES FOR WHILE LOOP*/ long long range1 = 9; int length = 1; /*FIND NUM'S LENGTH*/ while (NUM > range1) { long long range2 = range1 * 10 + 9; length += 1; …
Khalid Mukadam
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