#include <stdio.h>

int main(){
	int val = 0;
	scanf("%d",&val);
	
	int arr[val];
	for(int i = 0;i < val;i ++){
		scanf("%d",&arr[i]);
	}
	
	int minium = 0;
	for(int i = 1;i < val;i ++){
		int tmp = arr[i] - arr[i - 1];
		if(tmp < minium){
			minium = tmp;
		}
	}
	printf("%d",minium);
}