first bad version

Author: geeky01adarsh

README.md

@@ -5,4 +5,4 @@
 | S.No. | Topic | Status |
 |---|--------------|-----|
 |01. | [Array](https://github.com/geeky01adarsh/DSA-Interview-Questions/tree/main/Arrays) | 24/28 |
-|02. | [Searching](/Searching)|2/38|
+|02. | [Searching](/Searching)|3/38|

Searching/README.md

@@ -4,8 +4,8 @@
 |S.no.|Question|Solution|
 |---|------------|------------|
 |1|[Square Root](https://leetcode.com/problems/sqrtx/)|[Solution](sqrt.cpp)|
-|2| [First Bad Version](https://leetcode.com/problems/first-bad-version/)|[Solution](two_sum_ii_input_array_is_sorted.cpp)|
-|3| [Two Sum II - Input array is sorted](https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/)|Pending|
+|2| [First Bad Version](https://leetcode.com/problems/first-bad-version/)|[Solution](first_bad_version.cpp)|
+|3| [Two Sum II - Input array is sorted](https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/)|[Solution](two_sum_ii_input_array_is_sorted.cpp)|
 |4| [Valid Perfect Square](https://leetcode.com/problems/valid-perfect-square/)|Pending|
 |5| [Arranging Coins(Easy)](https://leetcode.com/problems/arranging-coins/)|Pending|
 |6| [Find Smallest Letter Greater Than Target](https://leetcode.com/problems/find-smallest-letter-greater-than-target/)|Pending|

Searching/first_bad_version.cpp

@@ -0,0 +1,39 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+vector<bool> check;
+
+bool isBadVersion(int n){
+    return check[n];
+}
+
+int firstBadVersion(int n)
+{
+    int low = 0, high = n;
+    while (low <= high)
+    {
+        int mid = low + (high - low) / 2;
+        if (!isBadVersion(mid))
+        {
+            if (!isBadVersion(mid + 1))
+                low = mid + 1;
+            else
+                return mid + 1;
+        }
+        else
+            high = mid - 1;
+    }
+    return -1;
+}
+
+int main(){
+    int n, x;
+    cin>>n>>x;
+    for(int i=0; i<n; i++){
+        if(i<x) check.push_back(0);
+        else check.push_back(1);
+    }
+
+    cout << firstBadVersion(n)<<endl;
+    return 0;
+}

Searching/two_sum_ii_input_array_is_sorted.cpp

@@ -2,44 +2,57 @@
 using namespace std;
 
 int binary_search(vector<int> arr, int n, int target, int i)
+{
+    int low = 0, high = n - 1;
+    while (low <= high)
     {
-        int low=0, high=n-1;
-        while(low<=high){
-            int mid = low+(high-low)/2;
-            if(arr[mid]==target)
-               { if(mid != i)return mid;
-                else if(arr[mid-1]==target) return mid-1;
-                else return mid+1;
-            }
-            else if(arr[mid]>target) high=mid-1;
-            else low = mid+1;
+        int mid = low + (high - low) / 2;
+        if (arr[mid] == target)
+        {
+            if (mid != i)
+                return mid;
+            else if (arr[mid - 1] == target)
+                return mid - 1;
+            else
+                return mid + 1;
         }
-        return -1;
+        else if (arr[mid] > target)
+            high = mid - 1;
+        else
+            low = mid + 1;
     }
-    vector<int> twoSum(vector<int>& num, int target) {
-        int n = num.size();
-        for(int i=0; i<n; i++){
-            int temp =binary_search(num, n, target-num[i], i);
-            if(temp!=-1)
-                return {i+1, temp+1};
-        }
-        return {-1, -1};
+    return -1;
+}
+
+vector<int> twoSum(vector<int> &num, int target)
+{
+    int n = num.size();
+    for (int i = 0; i < n; i++)
+    {
+        int temp = binary_search(num, n, target - num[i], i);
+        if (temp != -1)
+            return {i + 1, temp + 1};
     }
+    return {-1, -1};
+}
 
-int main(){
+int main()
+{
     int t;
-    cin>>t;
-    while(t--){
+    cin >> t;
+    while (t--)
+    {
         int n, target;
-        cin>>n>>target;
+        cin >> n >> target;
         vector<int> v;
-        for(int i=0; i<n; i++){
+        for (int i = 0; i < n; i++)
+        {
             int temp;
-            cin>>temp;
+            cin >> temp;
             v.push_back(temp);
         }
-        vector<int> ans=twoSum(v, target);
-        cout<<ans[0]<<" "<<ans[1]<<endl;
+        vector<int> ans = twoSum(v, target);
+        cout << ans[0] << " " << ans[1] << endl;
     }
     return 0;
 }