30 分 k=0暴力列舉 判斷

#include<iostream>
#include<cstdio>
#include<cstring>
using namespace std;
int n,k,fl,nw;
int a[1000009];
bool f[1000009];
int main() {
	freopen("diff.in","r",stdin);
	freopen("diff.out","w",stdout);
	int i,j;
	cin>>n>>k;
	for(i=1;i<=n;i++)
	  cin>>a[i];
	if(k==0) {
		for(i=1; ;i++) {
			fl=1;
			memset(f,0,sizeof(f));
			for(j=1;j<=n;j++) {
				nw=a[j]%i;
				if(f[nw]==0) f[nw]=1;
				  else {
				  	fl=0;
				  	break;
				  }
			}
			if(fl==1) {
				cout<<i;
				fclose(stdin);
				fclose(stdout);
				return 0;
			}
		}
    }
}