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copied!<p><code>-2147483648</code> is not a "number". C++ language does not support negative literal values.</p> <p><code>-2147483648</code> is actually an expression: a positive literal value <code>2147483648</code> with unary <code>-</code> operator in front of it. Value <code>2147483648</code> is apparently too large for the positive side of <code>int</code> range on your platform. If type <code>long int</code> had greater range on your platform, the compiler would have to automatically assume that <code>2147483648</code> has <code>long int</code> type. (In C++11 the compiler would also have to consider <code>long long int</code> type.) This would make the compiler to evaluate <code>-2147483648</code> in the domain of larger type and the result would be negative, as one would expect. </p> <p>However, apparently in your case the range of <code>long int</code> is the same as range of <code>int</code>, and in general there's no integer type with greater range than <code>int</code> on your platform. This formally means that positive constant <code>2147483648</code> overflows all available signed integer types, which in turn means that the behavior of your program is undefined. (It is a bit strange that the language specification opts for undefined behavior in such cases, instead of requiring a diagnostic message, but that's the way it is.)</p> <p>In practice, taking into account that the behavior is undefined, <code>2147483648</code> might get interpreted as some implementation-dependent negative value which happens to turn positive after having unary <code>-</code> applied to it. Alternatively, some implementations might decide to attempt using unsigned types to represent the value (for example, in C89/90 compilers were required to use <code>unsigned long int</code>, but not in C99 or C++). Implementations are allowed to do anything, since the behavior is undefined anyway.</p> <p>As a side note, this is the reason why constants like <code>INT_MIN</code> are typically defined as</p> <pre><code>#define INT_MIN (-2147483647 - 1) </code></pre> <p>instead of the seemingly more straightforward </p> <pre><code>#define INT_MIN -2147483648 </code></pre> <p>The latter would not work as intended.</p>

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