A parameter is declared as const, which means that changes are not allowed within the function, and constants and variables can be manipulated. On the contrary, not declaring it as const means that changes are allowed and only variables can be manipulated, not constants. In other words, const formal parameters can correspond to const and non-const actual parameters, but not vice versa.
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A parameter is declared as const, which means that changes are not allowed within the function, and constants and variables can be manipulated. On the contrary, not declaring it as const means that changes are allowed and only variables can be manipulated, not constants. In other words, const formal parameters can correspond to const and non-const actual parameters, but not vice versa.