WA on Chandu Returns

1

Problem : https://www.hackerearth.com/practice/algorithms/sorting/merge-sort/practice-problems/algorithm/chandu-and-his-girlfriend-returns/

My code : https://pastebin.com/bMYpZ5PK

Please find the error (logical or typo).

@everule1 @vijju1231 @ssjgz

2

I don’t think you know std::sort sorts in ascending order, not descending,

3

Oh yeah, just realised that. Sorry.

4

@everule1, even after reversing after sorting the array, it is giving WA.

5

second for loop n to n+m, not n to m.
also the faster approach is this

#include<bits/stdc++.h>
#include<iostream>
using namespace std;

int main(){
    int t;
    cin>>t;
    while(t--){
        int n,m;
        cin>>n>>m;
        int seq1[n];
        int seq2[m];
        for(int i=0;i<n;i++){
            cin>>seq1[i];
        }
        for(int i=0;i<m;i++){
            cin>>seq2[i];
        }
        int idx1=0;
        int idx2=0;
        for(int i=0;i<n+m;i++){
            if(idx1<n && idx2<m){
            if(seq1[idx1]>seq2[idx2]){
                cout<<seq1[idx1]<<" ";
                idx1++;
            }
            else{
                cout<<seq2[idx2]<<" ";
                idx2++;
            }
            }
            else if(idx1<n){
                cout<<seq1[idx1]<<" ";
                idx1++;
            }
            else{
                cout<<seq2[idx2]<<" ";
                idx2++;
            }
        }
        cout<<"\n";
    }
}
6

Works, thanks a lot !

7

Why don’t you try codechef questions.
Those 2-3 questions were very standard with little to learn

8

The problem is I’m a beginner, I really don’t know where to start from.
I’m following this flowchart : https://www.hackerearth.com/getstarted-competitive-programming/

I would surely like some guidance and suggestions from an expert.

9

I’m not an expert, Even i started 3 months ago. just very determined i guess.
I’ll give you 3 of favorite easy problems.

Try this. it’s really easy but it shows the usefulness of precomputation.

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