Help to solve ,please

Question

Write a function that converts given sequence by the following rules:
1 - If the letter is in upper case make it lower case;
2 - If the letter is in lower case make it upper case;
3 - If it's not a letter left it as is
Input:
The characters that have to be converted.
Input can contain any printeble characted(numbers,"[","]",")"),your task is to change only letters.
The size of the given sequence is not more that 100.
Output:
The proper sequence of characters(see the sample).

Input | Output
aBaBba | AbBbBA

#include<iostream>
#include<cstring>
using namespace std;
/*
* This function converts given sequence of characters
* from the lower case to upper case
*/
char convert(char arr) {
if ('a' <= arr && arr <= 'z') {
return char(arr - 32);
}
else {
return arr;
}
}
int main() {
char arr[1000];
cin >> arr;
int length = strlen(arr);
for (int i = 0; i < length; i++) {
cout << convert(arr[i]);
}
}

Answer 1

add an else if, to change upper to lower.
and change 'a' <= arr to arr => 'a' (more readable)

char convert(char arr) {
if (arr >= 'a' && arr <= 'z') {
return char(arr - 32);

}else if(arr >= 'A' && arr <= 'Z') {
return char(arr + 32);
}else {
return arr;
}

Answer 2

https://code.sololearn.com/c51fqdspiuMF/?ref=app

Answer 3

Thank you both!!!