Week1 CharanjeeevKaur

Week1/Count Negative Nos/CharanjeevKaur.txt

@@ -0,0 +1,22 @@
+class Solution {
+public:
+    int countNegatives(vector<vector<int>>& grid) 
+    {
+        int m  = grid.size();
+        int n = 0, count = 0;
+
+        for(int i = m-1;i >= 0;i--)
+        {
+            n = grid[i].size();
+            for(int j = n-1;j >= 0;j--)
+
+                if(grid[i][j] >= 0)
+                    break;
+                else
+                    count++;
+
+        }
+
+        return count;
+    }
+};

Week1/Missing no/CharanjeevKaur.txt

@@ -0,0 +1,15 @@
+class Solution 
+{
+    public:
+        int missingNumber(vector<int>& nums) 
+        {
+            int n=nums.size();
+
+            int sum = 0;
+            for(int i = 0;i < n; i++)
+                sum += nums[i];
+
+            int x= n*(n+1)/2;
+            return x-sum;
+        }
+};

Week1/Monotonic Array/CharanjeevKaur.txt

@@ -0,0 +1,25 @@
+class Solution {
+public:
+    bool isMonotonic(vector<int>& A) 
+    {
+        int n = A.size();
+        int count_inc = 1, count_dec = 1;
+
+        if(n == 1 || n == 2)
+            return true;
+
+        for(int i = 0; i < n-1; i++)
+        {
+            if(A[i] <= A[i+1])
+                count_inc++;
+
+            if(A[i] >= A[i+1])
+                count_dec++;
+        }
+
+        if(count_inc == n || count_dec == n)
+            return true;
+        else 
+            return false;
+    }
+};

Week1/Pivot Index/CharanjeevKaur.txt

@@ -0,0 +1,21 @@
+class Solution {
+public:
+
+    int pivotIndex(vector<int>& nums)
+    {
+        int lsum = 0, rsum = 0, n =nums.size();
+        for(int i = 0;i < n; i++)
+            rsum += nums[i];
+
+        for(int i = 0;i < n; i++)
+        {
+            rsum -= nums[i];
+            if(rsum == lsum)
+                return i;
+            lsum += nums[i];
+        }
+
+        return -1;
+
+    }
+};

Week1/Remove Duplicates/CharanjeevKaur.txt

@@ -0,0 +1,19 @@
+class Solution 
+{
+    public:
+        int removeDuplicates(vector<int>& nums) 
+        {
+            int j = 1, n = nums.size();
+            if(n == 0)
+                return 0;
+
+            for(int i = 0; i < n-1; i++)
+                if(nums[i] != nums[i+1])
+                {
+                    nums[j] = nums[i + 1];
+                    j++;
+                }
+
+            return j;
+        }
+};

Week1/Rotate Array/CharanjeevKaur.txt

@@ -0,0 +1,37 @@
+#include<iostream>
+#include<vector>
+
+using namespace std;
+
+class Solution {
+
+public:
+    void rotate(vector<int>& nums, int k) 
+    {
+            k=k%nums.size();
+            reverse(nums, 0, nums.size()-1);
+            reverse(nums, 0, k-1);
+            reverse(nums, k, nums.size()-1); 
+    }
+
+    void reverse(vector<int>& nums1, int i, int j)
+    {
+
+        while(i<j)
+        {
+            swap(nums1,i,j);
+            i++;
+            j--;
+        }
+
+    }
+
+    void  swap(vector<int>& nums2,int x,int y)
+    {
+        int temp;
+        temp=nums2[x];
+        nums2[x]=nums2[y];
+        nums2[y]=temp;
+    }
+
+}s;

Week1/Xor operation/CharanjeevKaur.txt

@@ -0,0 +1,13 @@
+class Solution {
+public:
+    int xorOperation(int n, int start) 
+    {
+        int result = start;
+        while(--n)
+        {
+            result = result ^ (start + 2 * n);
+        }
+
+        return result;
+    }
+};