# Look Back
```java
String s = "aabbbcdddee";
int count = 0;
char lastChar = s.charAt(0);
for (int i = 1; i < s.length(); i++) {
count++;
char thisChar = s.charAt(i);
if (thisChar != lastChar) {
System.out.print(lastChar + " " + count + " ");
count = 0;
lastChar = thisChar;
}
}
System.out.print(lastChar + " " + (count + 1));
```
# Look Ahead
```java
String s = "aabbbcdddee";
int count = 1;
for (int i = 0; i < s.length()-1; i++) {
if (s.charAt(i)==s.charAt(i+1)) {
count++;
} else {
System.out.print(s.charAt(i) + " " + count + " ");
count = 1;
}
}
System.out.print(s.charAt(s.length()-1) + " " + count + " ");
```