Nearest smaller to left

PHOTO EMBED

Fri Jun 17 2022 09:28:03 GMT+0000 (Coordinated Universal Time)

Saved by @Ranjan_kumar #c++

vector<int>v;
stack<int>s;

for(int i=0;i<n;i++)
{
   if(s.size()==0)
   {
      v.push_back(-1);
   }
   else if(s.size()>0&&s.top()<arr[i])
   {
      v.push_back(s.top())
   }
   else if(s.size()>0&&s.top()>=arr[i])
   {
      while(s.size()>0&&s.top>=arr[i])
      {
         s.pop();
      }
      if(s.size()==0)
      {
         v.push_back(-1);
      }
      else{
         v.push_back(s.top());
      }
   }
   s.push(arr[i]);
}
content_copyCOPY

https://www.youtube.com/watch?v=85LWui3FlVk&list=PL_z_8CaSLPWdeOezg68SKkeLN4-T_jNHd&index=4