#include
#include
using namespace std;

int countOccurrences(string str, char ch) {
int count = 0;
for (char c : str) {
if (c == ch) {
count++;
}
}
return count;
}

why you guyes dont use using namespace std ;

you removed "const" is this legal?

you can set range in regex like this:
std::regex("[1-4]")

simple as that... nice one

clever, very clever solution. congrats.

Just a slight difference in syntax, the algorithm is the same.

what does line 12 for (auto x : arr) do?

Edit: Just found the answer here , never heard of range-based loops before;

Oh, thank you kind stranger

Here rbegin() start from last it also called reverse beginning . Same for rend() also . Generally sort function return ascending order sort then descending is just reverse of it .

Thanks

What does .rbegin()/.rend() mean?

Thank you for the hint and link, I saw this kind of pattern a couple of times and didn't know what it was up till now, Danke.