Java practice recording 2020-05-01
Given a string, return a string made of the chars at indexes 0,1, 4,5, 8,9 ... so "kittens" yields "kien".
altPairs("kitten") → "kien"
altPairs("Chocolate") → "Chole"
altPairs("CodingHorror") → "Congrr"
public String altPairs(String str) {
String result = "";
// Run i by 4 to hit 0, 4, 8, ...
for (int i=0; i<str.length(); i += 4) {
// Append the chars between i and i+2
int end = i + 2;
if (end > str.length()) {
end = str.length();
}
result = result + str.substring(i, end);
}
return result;
}
