#include using namespace std; typedef signed long long ll; #undef _P #define _P(...) (void)printf(__VA_ARGS__) #define FOR(x,to) for(x=0;x>N; FOR(i,N) cin>>X[i]; ll ma=1LL<<40; sort(X,X+N); FOR(i,N-1) if(X[i]!=X[i+1]) ma=min(ma,X[i+1]-(ll)X[i]); if(ma==1LL<<40) ma=0; cout<