34A - Reconnaissance 2 - CodeForces Solution

// base template for CP

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define float double
#define sz 100005
#define all(a) a.begin(), a.end()
#define mod 1000000007
#define vi vector<int>
#define vvi vector<vector<int>>
#define debug cout << "here" << endl;
#define f(i,s,n) for (int i = s; i < n; ++i)
#define endl "\n"
#define br "\n"
#define printMap(mp) for(auto x : mp){cout<<x.first<<" : "<<x.second<<br;}
#define printv(v) for(auto x:v){cout<<x<<" ";}
#define printvv(v) for(auto x:v){{for(auto it:x) cout<<it<<" ";}cout<<br;}
#define readVector(v) f(i,0,v.size()) cin >> v[i]; 
#define w(t) while(t--)
const int inf = 4.5e18;
#define spc " "
/*
*max_element(arr, arr + n); 
int x = min_element(v.begin(),v.end()) - v.begin(); index of min element
string binary = std::bitset<64>(n).to_string(); decimal to binary
stoi(a, 0, 2);-->a is string of 0 and 1 -->gives decimal value
number of bits in number = > (int)log2(num)+1
vector <int> v[n]; // 2D vector of size n => vector<vector<int>> v(n);
bool flag = binary_search(v.begin(),v.end(), search_value);
int index = upper_bound(v.begin(), v.end(), search_value) - v.begin();
int index = lower_bound(v.begin(), v.end(), search_value) - v.begin();
gcd of two numbers = __gcd(a,b)

string line input
cin>>t; cin.ignore(); w(t--){string s; getline(cin,s);}

//string to lower case
transform(s.begin(), s.end(), s.begin(), ::tolower);

// global arr max size
    int arr[1e7];
    bool arr[1e8];
// inside finction arr max size
    int arr[1e6];
    bool arr[1e7];
*/

int32_t main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    int n;cin>>n;
    vi v(n); readVector(v);

      if(n==2){
        cout<<"1 2";
        return 0;
    }

    int idx=0;
    int diff = INT_MAX;
    f(i,1,n){
        int curr_diff = abs(v[i-1] - v[i]);
        if(curr_diff < diff){
            diff = curr_diff;
            idx=i;
        }
        if(diff==0)break;
    }

    if(abs(v[n-1] - v[0]) < diff){
        cout<<1<<spc<<n;
    }
    else cout<<idx<<spc<<idx+1;

    return 0;
}