Assigns new_value to all the elements in the range [first, last] that compare to old_value. The function use operator == to compare the individual elements to old_value
Function Template :
void replace (ForwardIterator first, ForwardIterator last, const T& old_value, const T& new_value) first, last : Forward iterators to the initial and final positions in a sequence of elelments. old_value : Value to be replaced. new_value : Replacement value.
Return Value :
This function do not return any value. If elements that needs to be replace is found then element
replaced otherwise remain unchanged.
Input : 10 20 30 30 20 10 10 20 Output : 10 99 30 30 99 10 10 99 // Replaced value 20 in vector to 99. Input : 3 5 7 8 9 5 4 Output : 3 5 7 12 9 5 4 // Replaced value 8 by 12.
Original Array: 10 20 30 30 20 10 10 20 New Array: 10 99 30 30 99 10 10 99
Assigns new_value to all the elements in range [first, last] for which pred returns true.
Function Template :
void replace_if (ForwardIterator first, ForwardIterator last, UnaryPredicate pred, const T& new_value) first, last : Forward iterators to the initial and final positions in a sequence of elelments. pred : Unary function that accepts an element in the range as argument, and returns a value convertible to bool.The returned value indicate whether the element is to be replaced (if true, it is replaced). The function shall not modify its argument. old_value : Value to be replaced. new_value : Replacement value.
Input : 1 2 3 4 5 6 7 8 9 10 Output : 0 2 0 4 0 6 0 8 0 10 // Replaced all odd values to 0. Input : 10 20 30 30 20 10 10 20 Output : 10 4 30 30 4 10 10 4 // Replaced all number divisible by 4 to 4.
Original Array: 1 2 3 4 5 6 7 8 9 10 New Array: 0 2 0 4 0 6 0 8 0 10
Also you can add any kind of function in std::replace_if that can only have one argument only.
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