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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#135697#5301. Modulo Ruins the LegendyuhuiWA 1ms3480kbC++142.2kb2023-08-05 22:29:122023-08-05 22:29:15

Judging History

你现在查看的是最新测评结果

  • [2023-08-10 23:21:45]
  • System Update: QOJ starts to keep a history of the judgings of all the submissions.
  • [2023-08-05 22:29:15]
  • 评测
  • 测评结果:WA
  • 用时:1ms
  • 内存:3480kb
  • [2023-08-05 22:29:12]
  • 提交

answer

#include<iostream>
using namespace std;
typedef long long ll;
const int MAXN = 100005;
int a[MAXN]={};
ll S = 0;
ll gcd(ll a,ll b)
{
    return b ? gcd(b,a%b) : a;
}
ll gcd(ll a,ll b,ll c)
{
    return gcd(a,gcd(b,c));
}
ll exgcd(ll a, ll b, ll &x, ll &y) {
    if (!b) {
        x = 1;
        y = 0;
        return a;
    }
    ll d = exgcd(b, a % b, x, y);
    ll t = x;
    x = y;
    y = t - (a / b) * y;
    return d;
}
// S = S%m N = n*(n+1)/2
// (S + n*s + N * d ) %m = ans    (ans-S) is a multiply of gcd(m,n,n*(n+1)/2)
// gcd(n,N)*t - my = ans - S  (A = n*s + n*(n+1)/2 * d = gcd(n,N)*t)
// gcd(n,N)*t - my = ans - S = k*gcd(n,N,m);
// ans = S + k*d
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    ll n = 0,m = 0;
    cin>>n>>m;
    ll N = n*(n+1)/2;
    for(int i=1;i<=n;++i){
        //cin>>a[i];
        S += a[i];
    }
    cin>>S;
    S%=m;
    if(n == 1 && S == 0){
        cout<<"0\n0 0\n";
        return 0;
    }
    ll d1 = gcd(n,N,m);
    ll d2 = gcd(n,N);
    ll k = S/d1;
    ll ans = S - k*d1;
    cout<<ans<<"\n";
    ll t = 0, y = 0;
    exgcd(d2,m,t,y);
    t = -t*k, y = -y*k;
    //t += 100*m/d1,y-=100*d2/d1;
    //cout<<t <<" "<<y <<" "<<t*d2 + m*y<<" "<<ans - S<<"\n";

    ll s = 0, d = 0;
    ll div = t/(m/d1);
    t -= div*m/d1;
    while(1){   
        
        ll A = t*d2;
        //cout<<t<<" "<<d2<<" "<<A<<"\n";
        exgcd(n,N,s,d);
        
        s = s*A/d2, d = d*A/d2;

        if(s < 0){
            ll mul = -s/(N/d2) + 1;
            s += mul*N/d2;
            d -= mul*n/d2;
        }
        if(d < 0){
            ll mul = -d/(n/d2) + 1;
            d += mul*n/d2;
            s -= mul*N/d2;
        }
        if(s >= m){
            ll mul = (s-m)/(N/d2) + 1;
            d += mul*n/d2;
            s -= mul*N/d2;
        }
        //cout<<s<<" "<<d<<" "<<t<<"\n";
        t += m/d1;
        if( s<0 || d<0 || s>m || d>m){continue;}
        cout<<s<<" "<<d<<"\n";
        //cout<<n*s + n*(n+1)/2 *d <<" "<<A<<"\n";
        //cout<< A<<" "<<y<<" "<<A - y*m <<" "<< ans - S<<"\n";
        //cout<< (S + n*s + N%m * d)%m<<"\n";
        break;
    }
}

Details

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Test #1:

score: 0
Wrong Answer
time: 1ms
memory: 3480kb

input:

6 24
1 1 4 5 1 4

output:

1
0 0

result:

wrong answer Result not equal to solution.