#include    <stdio.h>
#include    <stdlib.h>

int asc(const void *a, const void *b)
{
    return *(int*)a - *(int*)b;
}

int main(void)
{
    int N, X[100000];
    int i, j, min = 0, temp;

    scanf("%d", &N);
    for (i = 0; i < N; i++) {
        scanf("%d", &(X[i]));
    }

    qsort(X, N, sizeof(int), asc);

    min = 1000001;
    for (i = 0; i < N - 1; i++) {
        if (X[i] == X[i+1]) {
            continue;
        }
        if (min > (X[i+1] - X[i])) {
            min = X[i+1] - X[i];
        }
    }

    if (min != 1000001) {
        printf("%d\n", min);
    } else {
        printf("0\n");
    }

    return 0;
}