


How to Resolve the 'Expression Must Have a Constant Value' Error When Creating Arrays?
Expression Must Have a Constant Value
When trying to create an array using variables as the dimensions, users may encounter the error: "expression must have a constant value." This error signifies that the size of the array cannot be dynamically determined based on the variables.
To resolve this error, several approaches can be taken. One option is to create a dynamically allocated array using the new operator. This allows the array size to be determined at runtime. However, it is crucial to remember to manually free the allocated memory using delete when finished. Here's an example:
// Allocate the array int** arr = new int*[row]; for (int i = 0; i <p>Alternatively, if a fixed-size array is required, the array dimensions can be declared as const. This ensures that the array size remains constant and satisfies the compiler's requirement for a constant expression. Here's an example:</p><pre class="brush:php;toolbar:false">const int row = 8; const int col = 8; int arr[row][col];
Note that the code snippet you provided, int [row][col];, is incomplete as it does not specify a variable name for the array.
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MinGW - Minimalist GNU for Windows
This project is in the process of being migrated to osdn.net/projects/mingw, you can continue to follow us there. MinGW: A native Windows port of the GNU Compiler Collection (GCC), freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All MinGW software can run on 64-bit Windows platforms.
