Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

func nextInt(sc *bufio.Scanner) int {
	sc.Scan()
	i, err := strconv.Atoi(sc.Text())
	if err != nil {
		panic(err)
	}
	return i
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	for {
		m, nMin, nMax := nextInt(sc), nextInt(sc), nextInt(sc)
		if m == 0 && nMin == 0 && nMax == 0 {
			break
		}

		score_list := []int{}
		for i := 0; i < m; i++ {
			score_list = append(score_list, nextInt(sc))
		}

		// 最低合格者数と最高合格者数の間の各得点間のギャップが最大になる合格者数を取得する
		scoreGap := 0
		scoreGapMax := 0
		qualifiedNum := 0
		for n := nMin; n <= nMax; n++ {
			scoreGap = score_list[n-1] - score_list[n]
			if scoreGap >= scoreGapMax {
				scoreGapMax = scoreGap
				qualifiedNum = n
			}
		}

		fmt.Println(qualifiedNum)
	}
}

C++: #include<iostream>
#include<string.h>
#include<string>
#include<cstdio>
#include<algorithm>
#include<stack>
#include<queue>
#include<vector>
#include<cmath>
#include<utility>
#include<set>
#define ll long long int
#define ld long double
#define INF 1000000000
#define EPS 0.0000000001
#define rep(i,n) for(i=0;i<n;i++)
using namespace std;
typedef pair<int, int> pii;

int main()
{
  int m,nmin,nmax;
  int i,j;

  while(true){
    cin>>m>>nmin>>nmax;
    if(m==0 && nmin==0 && nmax==0)break;
    int score[200]={};
    rep(i,m)
      cin>>score[i];
    rep(i,m-1)
      score[i]-=score[i+1];

    pii p[200]={};
    int n=0;
    for(i=nmin-1;i<=nmax-1;i++){
      p[n].first=score[i];
      p[n].second=i+1;
      n++;
    }
    int num=nmax-nmin+1;
    sort(p,p+num);

    cout<<p[num-1].second<<endl;

  }

}

C++: #include "bits/stdc++.h"
using namespace std;
 
typedef long long ll;
typedef pair<int, int> pii;
 
#define FOR(i, s, e) for (int(i) = (s); (i) < (e); (i)++)
#define debug(x) cout << #x << ": " << x << endl
#define ALL(x) (x).begin(),(x).end()
 
const int INF = 1e9;
const ll LINF = 1e16;
 
int main() {
    cin.tie(0);
    ios_base::sync_with_stdio(false);
 
 
    while(1){
        int m, nmin, nmax;
        cin >> m >> nmin >> nmax;
        if (m == 0 && nmin == 0 && nmax == 0)break;
        vector<int> P(m);
        for (int i = 0; i < m; i++) cin >> P[i];
        int MAX = -1;
        int ret = 0;
        for (int i = nmin; i <= nmax; i++) {
            if (P[i - 1] - P[i] >= MAX) {
                MAX = P[i - 1] - P[i];
                ret = i;
            }
        }
        cout << ret << endl;
    }
     
  return 0;
}

C++: #include <bits/stdc++.h> // ver2.3.8
//#include <boost/math/tools/minima.hpp>
//#include <boost/multiprecision/cpp_int.hpp>
#define fmin brent_find_minima
#define int long long
#define endl "\n"
#define ALL(v) (v).begin(),(v).end()
#define COUNT(a,k) upper_bound(ALL(a),k)-lower_bound(ALL(a),k)
#define BIGGER(a,k) a.end()-upper_bound(ALL(a),k)
#define SMALLER(a,k) lower_bound(ALL(a),k)-a.begin()
#define Vi vector<int>
#define VVi vector<Vi>
#define Vs vector<string>
#define Pii pair<int,int>
#define VPii vector<Pii>
#define Tiii tuple<int,int,int>
#define VTiii vector<Tiii>
#define PQi priority_queue<int>
#define PQir priority_queue<int,vector<int>,greater<int>>
#define pb push_back
#define mp make_pair
#define mt make_tuple
#define itos to_string
#define stoi stoll
#define FI first
#define SE second
#define cYES cout<<"YES"<<endl
#define cNO cout<<"NO"<<endl
#define cYes cout<<"Yes"<<endl
#define cNo cout<<"No"<<endl
#define cyes cout<<"yes"<<endl
#define cno cout<<"no"<<endl
#define sortr(v) sort(v,greater<>())
#define rep(i,a,b) for(int i=a;i<b;i++)
#define repeq(i,a,b) for(int i=a;i<=b;i++)
#define repreq(i,a,b) for(int i=a;i>=b;i--)
#define leng(n) (int)(log10(n)+1)
#define dem(a,b) ((a+b-1)/(b))
#define Vin(a) rep(iI,0,a.size())cin>>a[iI]
#define INF 3000000000000000000  //  3.0*10^18(MAXの1/3くらい)
#define MAX LLONG_MAX
#define PI 3.141592653589793238462
#define MOD 1000000007  //  10^9 + 7

using namespace std;
/* fmin(f,L,R,100) で関数の最小値を(x,min)で返す　*/
//using boost::math::tools::brent_find_minima;
/* cpp_int (任意の長さのint) */
//using boost::multiprecision::cpp_int;

/* デバッグ用 */
void Vout(auto a){if(a.size()==0) cout<<"."<<endl;
else{rep(i,0,a.size()-1)cout<<a[i]<<' ';if(a.size()>0)cout<<a.back()<<endl;}return;}
void Verr(auto a){if(a.size()==0) cerr<<"."<<endl;
else{rep(i,0,a.size()-1)cerr<<a[i]<<' ';if(a.size()>0)cerr<<a.back()<<endl;}return;}
void VVout(auto a){if(a.size()==0)cout<<"."<<endl;
else{rep(i,0,a.size())Vout(a[i]);}return;}
void VVerr(auto a){if(a.size()==0)cerr<<"."<<endl;
else{rep(i,0,a.size())Verr(a[i]);}return;}
void VPout(auto a){if(a.size()==0)cout<<"."<<endl;
else{rep(i,0,a.size())cout<<a[i].FI<<' '<<a[i].SE<<endl;}return;}
void VPerr(auto a){if(a.size()==0)cerr<<"."<<endl;
else{rep(i,0,a.size())cerr<<a[i].FI<<' '<<a[i].SE<<endl;}return;}

/* 便利関数 */
int gcd(int a,int b){return b?gcd(b,a%b):a;} // 最大公約数gcd
int lcm(int a,int b){return a/gcd(a,b)*b;} // 最小公倍数lcm
int mypow(int x, int n, int m){ // 累乗x^n(mod m) O(log(n))
if(n==0)return 1;if(n%2==0)return mypow(x*x%m,n/2,m);else return x*mypow(x,n-1,m)%m;}
int scomb(int n, int r){if((n-r)<r)r=n-r; // nCr(小さい場合)
int a=1;for(int i=n;i>n-r;--i){a=a*i;}for(int i=1;i<r+1;++i){a=a/i;}return a;}
int comb(int n, int r){if((n-r)<r)r=n-r; // nCr(%MOD)
int a=1;for(int i=n;i>n-r;--i){a=a*i%MOD;}for(int i=1;
i<r+1;++i){a=a*mypow(i,MOD-2,MOD)%MOD;}return a%MOD;}
Vi stpowV(){Vi a(100001);
a[0]=1;repeq(i,1,100000)a[i]=a[i-1]*i%MOD;return a;}
//Vi stpow = stpowV();  // 階乗配列(%MOD)
Vi Vsum(Vi &v){Vi S(v.size()+1);rep(i,1,S.size())S[i]+=v[i-1]+S[i-1];return S;}// 累積和
int digit(int k,int i){string s = itos(k);return s[s.size()-i]-'0';} // i桁目の数字
void press(auto &v){v.erase(unique(ALL(v)),v.end());} // 圧縮
Vi zip(Vi b){int Z=b.size(); // 座標圧縮
Pii p[Z+10];int a=b.size();Vi l(a);for(int i=0;i<a;i++)
p[i]=mp(b[i],i);sort(p,p+a);int w=0;for(int i=0;i<a;i++)
{if(i&&p[i].first!=p[i-1].first)w++;l[p[i].second]=w;}return l;}
Vi beki2V(){Vi a(61);int q = 1;rep(i,0,61){a[i]=q;q*=2;}return a;}
//Vi beki2 = beki2V(); // 2^n配列
int modiv(int a,int b){return a*mypow(b,MOD-2,MOD)%MOD;} // a÷b(MOD環境)



signed main() {
  cin.tie(0);cout.tie(0);ios::sync_with_stdio(false);cout<<fixed<<setprecision(12);
  while(1){
    int m,nmin,nmax;
    cin >> m >> nmin >> nmax;
    if(m==0 && nmin == 0 && nmax==0) break;
    nmin--;
    Vi a(m);
    Vin(a);
    
    int ans = -1;
    int maxx = -1;
    rep(i,nmin,nmax){
      if(maxx <= a[i]-a[i+1]){
        maxx = a[i]-a[i+1];
        ans = i;
      }
    }
    cout << ans+1 << endl;
  }
  return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;
int main(){
  while(1){
        int m,n1,n2,ans,max=0,s,p;
        int a[10000];
        cin >> m >> n1 >> n2;
        if(m==0 && n1==0 && n2==0) break;
        for(int i=0; i<m; i++){
          cin >> p;
          a[i] = p;
        }
        for(int i=n1; i<=n2; i++){
          s = a[i-1] - a[i];
          if(s >= max) {
                ans = i;
                max = s;
          }
        }
        cout << ans << endl;
  }
  return 0;
}