#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define ull unsigned long long
//#define db double
#define all(x) x.begin(), x.end()
#define SZ(x) (int)(x.size())
#define mem(x, y) memset(x, y, sizeof(x))
#define what_is(x) cerr <<  "Line " << __LINE__ << ": " << #x << " is " << (x) << endl;
#define suf_zero(x) __builtin_ffs(x)
#define pre_zero(x) __builtin_clz(x)
#define num_one(x) __builtin_popcount(x)
#define error(args...) { string _s = #args; replace(_s.begin(), _s.end(), ',', ' '); stringstream _ss(_s); istream_iterator<string> _it(_ss); err(_it, args); }
#define mp make_pair
#define eb emplace_back
#define pb push_back
#define INFI 2000000009
#define INFLL (ll)1e18+7
#define fi first
#define se second
#define lson l, mid, rt<<1
#define rson mid+1, r, rt<<1|1
#define PII pair<int, int>
#define rep(i, begin, end) for(__typeof(end) i =(begin)-((begin)>(end));i!=(end)-((begin)>(end));i+=1-2*((begin)>(end)))
void err(istream_iterator<string> it) {cerr<<endl;}
template<typename T, typename... Args>
void err(istream_iterator<string> it, T a, Args... args) {
    cerr << *it << " = " << a << " , ";
    err(++it, args...);
}
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/tree_policy.hpp>
#include<ext/pb_ds/hash_policy.hpp>
using namespace __gnu_pbds;
//mt19937 rng32(chrono::steady_clock::now().time_since_epoch().count());
//mt19937_64 rng64(chrono::steady_clock::now().time_since_epoch().count());
const int mod = 1e9+7;
ll qp(ll b, ll n, const int mod){ll r=1;b%=mod;if(n<0) n+=mod-1;for(;n;n>>=1, b=b*b%mod)if(n&1) r=r*b%mod;return r;}
//#define RG register
///////////// BOUND /////////////////
//tree<ll, null_type, less<ll>, rb_tree_tag, tree_order_statistics_node_update> T;
namespace fastIO{
    #define BUF_SIZE 2000000
//     fread -> read
    bool IOerror = 0;
    static char obuf[BUF_SIZE], *OUT=obuf;
    inline char nc(){
        static char buf[BUF_SIZE], *p1 = buf+BUF_SIZE,
         *pend = buf+BUF_SIZE;
         if(p1==pend){
             p1 = buf;
             pend = buf+fread(buf, 1, BUF_SIZE, stdin);
             if(pend==p1){
                 IOerror = 1;
                 return -1;
             }
         }
         return *p1++;
    }
    inline bool blank(char ch){return ch==' '||ch=='\n'||ch=='\r'||ch=='\t';}
    inline int read(int &x){
        char ch;
        while(blank(ch=nc()));
        if(IOerror)return 0;
        for(x=ch-'0';(ch=nc())>='0'&&ch<='9';x=x*10+ch-'0');
        return 1;
    }
    inline int read(ll &x){
        char ch;
        while(blank(ch=nc()));
        if(IOerror)return 0;
        for(x=ch-'0';(ch=nc())>='0'&&ch<='9';x=x*10+ch-'0');
    }
    void print(const int& x) {
        if(x > 9) print(x / 10);
        *OUT++= x % 10 + '0';
    }
    void print(const ll& x) {
        if(x > 9) print(x / 10);
        *OUT++= x % 10 + '0';
    }
    void print(const char*s)
    {
        int len = strlen(s);
        for(int i=0;i<len;++i) *(OUT++) = s[i];
    }
    //void print(const __int128& x){if(x>9)print(x/10);putchar('0'+x%10);}
    void print(){fwrite(obuf, OUT-obuf, 1, stdout);}
    #undef BUF_SIZE
};
using namespace fastIO;
/////////////// MACRO ///////////////
int a[1010];
int main()
{
    int n;scanf("%d", &n);
    for(int i=1;i<=n;++i)
    scanf("%d", &a[i]);
    ll ans = INFI;
    for(int i=-100;i<=100;++i)
    {
        ll tmp = 0;
        for(int j=1;j<=n;++j)
            tmp += (a[j]-i)*(a[j]-i);
        ans = min(ans, tmp);
    }
    cout << ans << endl;
}

Measured memory_bytes: 256