Have the function RunLength(str) take the str parameter being passed and return a compressed version of the string using the Run-length encoding algorithm. This algorithm works by taking the occurrence of each repeating character and outputting that number along with a single character of the repeating sequence.
For example:
"wwwggopp" would return 3w2g1o2p. The string will not contain any numbers, punctuation, or symbols.Run length coderbyte java
import java.util.Scanner;
public class RunLength {
String RunLength(String str) {
StringBuilder result = new StringBuilder("");
char[] chars = str.toCharArray();
char previousChar = chars[0];
int charCount = 1;
for (int i = 1; i < chars.length; i++) {
if (chars[i] == previousChar) {
charCount++;
} else {
result.append(charCount).append(previousChar);
charCount = 1;
previousChar = chars[i];
}
if (i == chars.length - 1) {
result.append(charCount).append(previousChar);
}
}
return result.toString();
}
public static void main (String[] args) {
// keep this function call here
Scanner s = new Scanner(System.in);
RunLength c = new RunLength();
System.out.print(c.RunLength(s.nextLine()));
}
}
Run length coderbyte python
def RunLength(a_str):
compressed_string = ''
start_indices = get_new_letter_start_indices(a_str)
string_end_index = len(a_str)
start_indices.append(string_end_index)
for index in range(len(start_indices) - 1):
num_occurrences = start_indices[index + 1] - start_indices[index]
letter = a_str[start_indices[index]]
compressed_string += (str(num_occurrences) + letter)
return compressed_string
def get_new_letter_start_indices(a_str):
letter_start_indices = [0]
for index in xrange(1, len(a_str)):
if a_str[index] != a_str[index - 1]:
letter_start_indices.append(index)
return letter_start_indices
# keep this function call here
# to see how to enter arguments in Python scroll down
print RunLength(raw_input())
