Question description
My code
public class Solution {
public String decodeString(String s) {
StringBuilder sb = new StringBuilder(s);
for (int i = 0; i < sb.length(); i++) {
char c1 = sb.charAt(i);
if (c1 == '[') {
for (int j = i + 1; j < sb.length(); j++) {
char c2 = sb.charAt(j);
if (c2 == ']') {
int begin = 0;
for (int k = i - 1; k >= 0; k --) {
if (sb.charAt(k) > 57) {
begin = k + 1;
break;
}
}
int num = Integer.parseInt(sb.substring(begin, i));
String sub = sb.substring(i + 1, j);
StringBuilder tmp = new StringBuilder();
for (int k = 0; k < num; k++) {
tmp.append(sub);
}
sb.replace(begin, j + 1, tmp.toString());
i = 0;
break;
} else if (c2 == '[') {
break;
}
}
}
}
return sb.toString();
}
}
Solution
For brackets that have no inside brackets, directly multiply the content in the bracket by the number before the bracket. Otherwise, look into the bracket and get the bracket without inner brackets.