Consecutive Character Blocks ā Problem Statement & Solution Guide
Problem Description
Given a string of characters, count the number of blocks where a character is immediately followed by the same character, ignoring isolated characters without consecutive duplicates.
Examples
Input
aaabbbccc
Output
2
Explanation: Step-by-step: 1. Initialize a counter for consecutive blocks. 2. Iterate over the string, checking for consecutive characters. 3. If a character is the same as the previous one, increment the counter. 4. If a character is different from the previous one, reset the counter. 5. After iterating over the entire string, return the counter.
Input
abc
Output
0
Explanation: Step-by-step: 1. Initialize a counter for consecutive blocks. 2. Iterate over the string, checking for consecutive characters. 3. Since 'a' and 'b' are not consecutive, reset the counter. 4. Since 'b' and 'c' are not consecutive, reset the counter. 5. After iterating over the entire string, return the counter.
Constraints
- 1 <= transmission string length <= 1000
- Transmission string only contains uppercase English letters
Optimal Approach & Strategy
An optimized approach involves using a single loop to iterate through the transmission string, keeping track of the current character and the count of consecutive occurrences. This approach allows us to identify signal blocks in a single pass through the string, resulting in a much more efficient solution. The optimized approach can be implemented using a simple loop and conditional statements.
Brute Force Approach
A brute-force approach would involve comparing each character with every other character in the string, resulting in a time complexity of O(nĀ²). However, this approach is inefficient and would not be suitable for large transmission strings. The brute-force approach can be implemented using nested loops to compare characters and count signal blocks.
Verified Code Solutions
function countBlocks(s) {
let count = 0, i = 0;
while (i < s.length) {
if (i < s.length - 1 && s[i] === s[i + 1]) {
let j = i + 1;
while (j < s.length && s[j] === s[i]) {
j++;
}
count++;
i = j;
} else {
i++;
}
}
return count;
}public int consecutiveBlocks(String s) {
if (s == null || s.length() == 1) {
return 0;
}
int count = 1;
int maxCount = 1;
for (int i = 1; i < s.length(); i++) {
if (s.charAt(i) == s.charAt(i - 1)) {
count++;
} else {
maxCount = Math.max(maxCount, count);
count = 1;
}
}
return Math.max(maxCount, count);
}def consecutive_blocks(s: str) -> int:
if not s or len(s) == 1:
return 0
count = 1
max_count = 1
for i in range(1, len(s)):
if s[i] == s[i - 1]:
count += 1
else:
max_count = max(max_count, count)
count = 1
return max(max_count, count)function countBlocks(s) {
let count = 0, i = 0;
while (i < s.length) {
if (i < s.length - 1 && s[i] === s[i + 1]) {
let j = i + 1;
while (j < s.length && s[j] === s[i]) {
j++;
}
count++;
i = j;
} else {
i++;
}
}
return count;
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