// editor3
#include<stdio.h>
#define MAX 12 
int main(){
    int K;
    if (scanf("%d", &K) != 1 || K < 4 || K >12)
    {
        printf("Invalid input");
        return 0;
        
    }
    int pulses[K];
    for (int i = 0; i < K; i++)
    {
        if (scanf("%d",&pulses[i]) != 1 || pulses[i] < 1 || pulses[i] > 5000)
        {
            printf("Invalid input");
            return 0;
        }
    }
    int accepted[K],count = 0;
    int sum = 0  , max = 0 ;
    for(int i = 0; i < K; i+ ){
        if (pulses[i] > max){
            accepted[count++] = pulses[i];
            max = pulses[i];
        }
    }
    if (count ==0){
        printf("Invalid input");
        return 0;
    }
    int min = accepted[0] ;
    int max = accepted[0];
    for (int i = 1; i < count; i++){
        if (accepted[i] < min)min=accepted[i];
    printf("%d",max - min);
    return 0;
    }
}