Create day005sol01.cpp

Author: Naman2251

Problems/Data-structures/Day-05/sol/Naman2251/day005sol01.cpp

@@ -0,0 +1,44 @@
+//Submission Link: https://cses.fi/problemset/result/15792090/
+
+/*
+we are going through the array ans checking if the number right left to it is smaller to it then answer for that is (i-1) else we will check position ans[i-1]
+if we encounter ans[i]=-1 we know there is no number smaller than that so the ans is -1
+*/
+
+#include<bits/stdc++.h>
+using namespace std;
+void solve(){
+    int n;
+    cin>>n;
+    vector<int> vec(n);
+    for(int i=0;i<n;i++){
+        cin>>vec[i];
+    }
+    vector<int> ans(n);
+    ans[0]=-1;
+    for(int i=1;i<n;i++){
+        if(vec[i]>vec[i-1]){
+            ans[i]=i-1;
+        }else{
+            int a=ans[i-1];
+            bool ok=true;
+            while(a>-1){
+                if(vec[a]<vec[i]){
+                    ans[i]=a;
+                    ok=false;
+                    break;
+                }
+                a=ans[a];
+            }
+            if(ok) {
+                ans[i]=-1;
+            }
+        }
+    }
+    for(int i=0;i<n;i++){
+        cout<<ans[i]+1<<" ";
+    }
+}
+int main(){
+    solve();
+}