first negative in window size k along with 3 LC

Author: Adityasinghvats

23queue/08first_negative.cpp

@@ -0,0 +1,27 @@
+#include<bits/stdc++.h>
+//find first negative in window of size k
+using namespace std;
+int main(){
+    vector<int> v {0,-1,-2,3,4,-5,6,7,-8};
+    int k = 2; //window size
+    //find all negative index and fill in queue
+    queue<int> q;
+    for(int i=0;i<v.size();i++){
+        if(v[i]<0) q.push(i);
+    }// q = {1,2,5,8}
+
+    vector<int> ans;
+    for(int i=0;i<=v.size()-k;i++){
+        // in case start of window is aheead of idx in queue
+        while(q.size()>0 && q.front()<i) q.pop();
+        // // in case end of window is aheead of idx in queue
+        if(q.size()==0 || q.front()>=i+k) ans.push_back(0);
+        else{
+            int idx = q.front();
+            ans.push_back(v[idx]);
+        }
+    }
+    for(int ele:ans){
+        cout<<ele<<" ";
+    }
+}