#include <iostream>
#include <cstdio>
#include <string>
#include <vector>
#include <map>
#include <algorithm>
#include <set>
#include <bitset>
#include <cmath>

using namespace std;

int main() {
	vector<int> a;
	//int x;
	while(cin){
		int x;
		cin >> x;
		if(x ==0){
			break;
		}
		a.push_back(x);
	}
	int buf = 0;
	vector <int> b;
	for(int i = 1; i < a.size() - 1; i++){
		if(a[i] > a[i - 1] && a[i] > a[i + 1]){
			//buf++;
			b.push_back(i);

		}
	}
	if(b.size() == 0 || b.size() == 1){
		cout << 0;
		return 0;
	}
	int min = 1e9;
	for(int i = 0; i < b.size() - 1; i++){
		if(b[i + 1] - b[i] < min){
			min = b[i + 1] - b[i];
		}
	}
	cout << min;
}