946. Distinct Substrings (LeetCode 1698)

Given a string s, return the number of distinct substrings of s. A string substring is a contiguous sequence of characters within the string.

🧠 Visual Learning Aid

💡 Approach

• → Use DP where dp[i] represents number of distinct substrings ending at position i
• → For each position, consider all possible endings of substrings
• → Use hash set to track seen substrings
• → Time: O(n²), Space: O(n²)
• → Alternative approach: Use suffix automaton or suffix array for O(n) solution

🧭 Prerequisites

🛠️ Hints & Pitfalls

Hints

• •Use DP where dp[i] represents number of distinct substrings ending at position i
• •For each position, consider all possible endings of substrings
• •Use hash set to track seen substrings

Common Pitfalls

• •Time: O(n²), Space: O(n²)
• •Alternative approach: Use suffix automaton or suffix array for O(n) solution

🧪 Test Cases

Hidden tests on submit: 1

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