Submission #4277854

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Source Code Expand

#include<bits/stdc++.h>
#define X first
#define Y second
#define pb emplace_back
#define FOR(i,a,b) for(int (i)=(a);i<(b);++(i))
#define EFOR(i,a,b) for(int (i)=(a);i<=(b);++(i))
#define rep(X,Y) for (int (X) = 0;(X) < (Y);++(X))
#define reps(X,S,Y) for (int (X) = S;(X) < (Y);++(X))
#define rrep(X,Y) for (int (X) = (Y)-1;(X) >=0;--(X))
#define rreps(X,S,Y) for (int (X) = (Y)-1;(X) >= (S);--(X))
#define all(X) (X).begin(),(X).end()
#define rall(X) (X).rbegin(),(X).rend()
#define eb emplace_back
#define UNIQUE(X) (X).erase(unique(all(X)),(X).end())

using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef ll LL;
typedef pii PII;
typedef pll PLL;
template<class T> using vv=vector<vector<T>>;
template<class T> inline bool MX(T &l,const T &r){return l<r?l=r,1:0;}
template<class T> inline bool MN(T &l,const T &r){return l>r?l=r,1:0;}
const ll MOD=1e9+7;
const LL INF = 1e11;
int N;
map<LL, int> cnt;

const LL L = 2155;
const int M = 100001;
bool is_composite[M];
vector<LL> ps, tris;
map<LL, LL> sq2p, p2sq;

LL Reduce(LL v) {
  for (LL p : tris) {
    while (v%p == 0) v /= p;
  }
  return v;
}

LL Rev(LL v) {
  LL ret = 1;
  for (LL p : ps) {
    int e = 0;
    while (v%p == 0) {
      e++;
      v /= p;
    }

    assert(e <= 2);
    if (e == 1) ret *= p*p;
    else if (e == 2) ret *= p;
  }

  if (1 < v) { 
    assert(v > 2000);
    if (sq2p.count(v)) v = sq2p[v];
    else if (p2sq.count(v)) v = p2sq[v];
    else return -1;
    ret *= v;
  } 

  return ret;
}

int main() {
  reps(i, 2, M) {
    if (is_composite[i]) continue;
    LL p = i;
    if (p < L) {
      ps.eb(p);
      tris.eb(p*p*p);
    } else {
      sq2p[p*p] = p;
      p2sq[p] = p*p;
    }

    for (int j=i+i; j<M; j+=i) {
      is_composite[j] = true;
    }
  }
  //cout << ps.size() << endl;

  scanf("%d", &N);
  rep(i, N) {
    LL s;
    scanf("%lld", &s);
    cnt[Reduce(s)]++;
  }

  int ans = N;
  for (auto &p : cnt) {
    LL v = p.X;
    int a = p.Y;
    //printf("%lld: %d\n", v, a);
    LL r = Rev(v);
    if (!cnt.count(r)) continue;
    int b = cnt[r];
    if (a > b) continue;
    if (a == b && v < r) continue;
    if (a == b && v == r) assert(v == 1);
    //printf("removed (%lld,%d) because of (%lld, %d)\n", v, a, r, b);
    ans -= a;
  }

  if (cnt.count(1)) ans++;
  printf("%d\n", ans);
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:87:18: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &N);
                  ^
./Main.cpp:90:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
     scanf("%lld", &s);
                      ^

Judge Result