Merge branch 'coder2hacker:main' into main

Author: syndax9

Longest_Substring.cpp

@@ -0,0 +1,41 @@
+// C++ program to find the length of the longest substring
+// without repeating characters
+#include <bits/stdc++.h>
+using namespace std;
+// This function returns true if all characters in str[i..j]
+// are distinct, otherwise returns false
+bool areDistinct(string str, int i, int j)
+{
+	vector<bool> visited(26);
+	for (int k = i; k <= j; k++) {
+		if (visited[str[k] - 'a'] == true)
+			return false;
+		visited[str[k] - 'a'] = true;
+	}
+	return true;
+}
+
+// Returns length of the longest substring
+// with all distinct characters.
+int longestUniqueSubsttr(string str)
+{
+	int n = str.size();
+	int res = 0; // result
+	for (int i = 0; i < n; i++)
+		for (int j = i; j < n; j++)
+			if (areDistinct(str, i, j))
+				res = max(res, j - i + 1);
+	return res;
+}
+
+// Driver code
+int main()
+{
+	string str = "bobisbobbydeol";
+	cout << "The input string is " << str << endl;
+	int len = longestUniqueSubsttr(str);
+	cout << "The length of the longest non-repeating "
+			"character substring is "
+		<< len;
+	return 0;
+}

Trapping_Rain_water

@@ -0,0 +1,26 @@
+class Solution {
+public:
+    int trap(vector<int>& height) {
+        int n = height.size();
+        vector<int>l(n,height[0]);
+        vector<int>r(n,height[n-1]);
+        
+        int lm = height[0];
+        for(int i = 1;i<n;i++){
+            lm = max(lm,height[i]);
+            l[i] = lm;
+        }
+        int rm = height[n-1];
+        for(int i = n-2;i>=0;i--){
+            rm = max(rm,height[i]);
+            r[i] = rm;
+        }
+        
+        int ans = 0;
+        for(int i = 0;i<n;i++){
+            ans += (min(r[i],l[i])-height[i]);
+        }
+        
+        return ans;
+    }
+};