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 < row; i++)
    arr[i] = new int[col];

// Use the array

// Deallocate the array
for (int i = 0; i < row; i++)
    delete[] arr[i];
delete[] arr;

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:

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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