#include <stdio.h>
int main(void){
    int n;
    scanf( "%d", &n );

    int i, j;
    int x;
    int pos[n];
    long min = 1000000;
    int d = 0;

    for( i = 0; i < n; i++ ){
        scanf( "%d", &x );
        pos[i] = x;
    }
    for( i = 0; i < n; i++ ){
        for( j = i + 1; j < n; j++ ){
            d = pos[i] - pos[j];
            d = d < 0 ? d * -1 : d;
            if( d > 0 && d < min ){
                min = d;
            }
        }
    }
    printf( "%d\n", min );
}