Submission #856278

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Source Code Expand

#include <iostream>
#include <iomanip>
#include <vector>
#include <algorithm>
#include <numeric>
#include <functional>
#include <cmath>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <sstream>
#include <string>
#define repd(i,a,b) for (int i=(int)(a);i<(int)(b);i++)
#define rep(i,n) repd(i,0,n)
#define all(x) (x).begin(),(x).end()
#define mod 1000000007
#define inf 2000000007
#define mp make_pair
#define pb push_back
typedef long long ll;
using namespace std;
template <typename T>
inline void output(T a, int p) {
    if(p) cout << fixed << setprecision(p)  << a << "\n";
    else cout << a << "\n";
}
// end of template

vector<ll> dec(ll n){
    vector<ll> ret;
    for(ll i = 1; i * i <= n; i++){
        if(n % i == 0){
            if(n / i == i) ret.pb(i);
            else ret.pb(i), ret.pb(n / i);
        }
    }
    sort(all(ret));
    return ret;
}

bool ok(ll b, ll n, ll s){ // nをb進法したものの各桁の和はsか?
    ll ret = 0;
    while(n > 0){
        ret += n % b;
        n /= b;
    }
    if (ret == s) return true;
    else return false;
}

int main() {
    cin.tie(0);
    ios::sync_with_stdio(0);
    // source code
    ll n, s;
    cin >> n >> s;
    if(n == s){
        output(n + 1, 0);
        return 0;
    }
    if(n < s){
        output(-1, 0);
        return 0;
    }
    vector<ll> D = dec(n - s);
    rep(i, D.size()) D[i]++;
    rep(i, D.size()){
        if(ok(D[i], n, s)){
            output(D[i], 0);
            return 0;
        }
    }
    output(-1, 0);
    
    return 0;
}

Submission Info

Judge Result