Java Binary String Addition with Carry Logic

🚀 Day 28 / 180 – DSA with Java 🚀 📘 Topic Covered: Strings & Sliding Window 🧩 Problem Solved: Divisor Substrings Problem: Given an integer num and an integer k, find the number of substrings of length k from the digits of num such that the substring value divides num. Approach: Converted the number to a string and used a sliding window of size k to extract substrings. Each substring was converted back to an integer and checked whether it divides the original number. Key Learning: ✔️ Applying sliding window technique on strings ✔️ Converting between numeric and string representations ✔️ Handling edge cases like division by zero If you’re also preparing for DSA, let’s connect and learn together 🤝 #DSA #Java #180DaysOfCode #LearningInPublic #Strings #ProblemSolving #Consistency

🚀 Day 27 / 180 – DSA with Java 🚀 📘 Topic Covered: Strings & Reverse Traversal 🧩 Problem Solved: Length of Last Word Problem: Given a string containing words separated by spaces, find the length of the last word. Approach: Started traversing the string from the end, skipped trailing spaces first, and then counted characters until encountering another space or reaching the beginning of the string. Key Learning: ✔️ Efficient reverse traversal in strings ✔️ Handling edge cases like trailing spaces ✔️ Writing simple yet optimized string logic If you’re also preparing for DSA, let’s connect and learn together 🤝 #DSA #Java #180DaysOfCode #LearningInPublic #Strings #ProblemSolving #Consistency

🚀 Day 34 / 180 – DSA with Java 🚀 📘 Topic Covered: Arrays & Basic Construction 🧩 Problem Solved: Concatenation of Array Problem: Given an integer array nums, create a new array that contains the elements of nums twice in sequence. Approach: Created a new array with double the size of the original array and filled the first half with the original elements, then copied the same elements again into the second half. Key Learning: ✔️ Practicing array construction and indexing ✔️ Understanding how to manipulate array sizes ✔️ Writing clean logic for simple transformation problems If you’re also preparing for DSA, let’s connect and learn together 🤝 #DSA #Java #180DaysOfCode #LearningInPublic #Arrays #ProblemSolving #Consistency 

🚀 Day 33 / 180 – DSA with Java 🚀 📘 Topic Covered: Arrays & Index Manipulation 🧩 Problem Solved: Shuffle the Array Problem: Given an array in the form [x1, x2, ..., xn, y1, y2, ..., yn], rearrange it to [x1, y1, x2, y2, ..., xn, yn]. Approach: Used two pointers to track elements from the first and second halves of the array, then alternately placed them into a new array to achieve the required shuffle pattern. Key Learning: ✔️ Managing multiple pointers in array problems ✔️ Practicing index-based rearrangement ✔️ Maintaining correct ordering while constructing a new array If you’re also preparing for DSA, let’s connect and learn together 🤝 #DSA #Java #180DaysOfCode #LearningInPublic #Arrays #ProblemSolving #Consistency

🚀 Day 30 / 180 – DSA with Java 🚀 📘 Topic Covered: Strings & Sorting Technique 🧩 Problem Solved: Longest Common Prefix Problem: Given an array of strings, find the longest common prefix shared among all the strings. Approach: Sorted the array of strings and compared only the first and last strings. Since sorting groups similar prefixes together, the common prefix between these two strings represents the common prefix for the entire array. Key Learning: ✔️ Using sorting to simplify string comparison problems ✔️ Observing patterns to reduce unnecessary checks ✔️ Efficient prefix detection in string arrays If you’re also preparing for DSA, let’s connect and learn together 🤝 #DSA #Java #180DaysOfCode #LearningInPublic #Strings #ProblemSolving #Consistency 

🚀 Day 31 / 180 – DSA with Java 🚀 📘 Topic Covered: Strings & Substring Search 🧩 Problem Solved: Find the Index of the First Occurrence in a String Problem: Given two strings haystack and needle, return the index of the first occurrence of needle in haystack. If it is not present, return -1. Approach: Traversed the main string and checked potential starting positions where the first character matched. Then compared the substring of the same length as the target string to verify a complete match. Key Learning: ✔️ Understanding substring search logic ✔️ Optimizing comparisons by checking the first character first ✔️ Practicing careful boundary handling in string traversal If you’re also preparing for DSA, let’s connect and learn together 🤝 #DSA #Java #180DaysOfCode #LearningInPublic #Strings #ProblemSolving #Consistency 

🚀 Day 22 / 180 – DSA with Java 🚀 📘 Topic Covered: Hashing & Sequence Detection 🧩 Problem Solved: Longest Consecutive Sequence Problem: Given an unsorted array of integers, find the length of the longest consecutive elements sequence in O(n) time. Approach: Stored all elements in a HashSet for O(1) lookups. For each number, only started counting if it was the beginning of a sequence (i.e., the previous number was not present). Then extended the sequence forward to find its length. Key Learning: ✔️ Using HashSet for efficient lookups ✔️ Identifying sequence starting points to avoid redundancy ✔️ Achieving O(n) time complexity for an otherwise sorting-based problem If you’re also preparing for DSA, let’s connect and learn together 🤝 #DSA #Java #180DaysOfCode #LearningInPublic #Hashing #ProblemSolving #Consistency

🚀 Day 19 / 180 – DSA with Java 🚀 📘 Topic Covered: Strings & Greedy Traversal 🧩 Problem Solved: Largest Odd Number in a String Problem: Given a numeric string, return the largest-valued odd-numbered substring. If no odd digit exists, return an empty string. Approach: Traversed the string from right to left to find the first odd digit. Once found, returned the substring from the start up to that index to ensure the largest possible odd number. Key Learning: ✔️ Observing patterns to reduce unnecessary computation ✔️ Efficient right-to-left traversal ✔️ Applying greedy thinking in string problems If you’re also preparing for DSA, let’s connect and learn together 🤝 #DSA #Java #180DaysOfCode #LearningInPublic #Strings #ProblemSolving #Consistency

🚀 Day 29 / 180 – DSA with Java 🚀 📘 Topic Covered: Arrays & Two-Pointer Technique 🧩 Problem Solved: Container With Most Water Problem: Given an array where each element represents the height of a vertical line, find two lines that together with the x-axis form a container that holds the maximum amount of water. Approach: Used a two-pointer strategy starting from both ends of the array. Calculated the water area using the shorter height and the distance between pointers, then moved the pointer with the smaller height to try finding a better container. Key Learning: ✔️ Efficient use of two-pointer technique ✔️ Understanding how pointer movement impacts optimization ✔️ Reducing brute-force O(n²) solutions to O(n) If you’re also preparing for DSA, let’s connect and learn together 🤝 #DSA #Java #180DaysOfCode #LearningInPublic #Arrays #ProblemSolving #Consistency

🚀 DSA in Java – Day 84 Today’s problem was all about matrix rotation and pattern matching 🧠💡 🔍 Problem: Determine whether a given matrix can be rotated (0°, 90°, 180°, 270°) to match a target matrix. 💡 Key Learning: Matrix rotation is a pattern-based transformation problem Instead of manually checking all possibilities, we can: ✔ Rotate the matrix step by step ✔ Compare after each rotation Clean logic + iteration = efficient solution 🛠 Approach: Rotate matrix 4 times (0°, 90°, 180°, 270°) After each rotation, check if it matches the target If match found → return true, else false 📈 What I improved today: Matrix manipulation skills Thinking in rotations & transformations Writing clean and reusable functions 🔥 Consistency is the key! Day 84 done, moving closer to mastery. #DSA #Java #100DaysOfCode #CodingJourney #LeetCode #ProblemSolving #WomenInTech