# Run-Length Decoding- Google Top Interview Questions

### Problem Statement :

```Given a string s, consisting of digits and lowercase alphabet characters, that's a run-length encoded string, return its decoded version.

Note: The original string is guaranteed not to have numbers in it.

Constraints

0 ≤ n ≤ 100,000 where n is the length of s

Example 1

Input

s = "4a3b2c1d2a"

Output

"aaaabbbccdaa"```

### Solution :

```                        ```Solution in C++ :

string solve(string s) {
int l = 0, temp;
string ans = "";
for (char c : s) {
temp = c - '0';
if (temp >= 0 && temp <= 9)
l = l * 10 + temp;
else {
while (l--) ans += c;
l = 0;
}
}
return ans;
}```
```

```                        ```Solution in Java :

import java.util.*;

class Solution {
public String solve(String s) {
StringBuilder sb = new StringBuilder();
int v = 0;

for (int i = 0; i < s.length(); i++) {
char c = s.charAt(i);
if (Character.isDigit(c)) {
v = (v * 10) + Integer.parseInt("" + c);
} else {
for (int k = 0; k < v; k++) {
sb.append(c);
}
v = 0;
}
}

return sb.toString();
}
}```
```

```                        ```Solution in Python :

class Solution:
def solve(self, s):
ans = ""
c = ""
for i in range(len(s)):
if s[i].isalpha():
ans = ans + int(c) * s[i]
c = ""
else:
c = c + s[i]

return ans```
```

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