Run-Length String Compression

Implement run-length string compression. Scan a string s from left to right and group consecutive identical characters: If a character occurs once in its consecutive group, output the character itself. If it occurs more than once, output the character followed by its count. For example, aaaaabbbccca becomes a5b3c3a. Input One non-empty string s containing printable ASCII characters other than newline. Output The compressed string. Constraints 1 <= |s| <= 2 * 10^5 Example Input aaaaabbbccca Output a5b3c3a