oj.uz

Submission #586926

# Submission time Handle Problem Language Result Execution time Memory
586926 2022-07-01T05:19:57 Z 반딧불(#8396) Mixture (BOI20_mixture) C++17
0 / 100
 1 ms 304 KB 
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

struct Frac{
    ll a, b;
    Frac(){}
    Frac(ll a, ll b): a(a), b(b){
        ll g = __gcd(a, b);
        a/=g, b/=g;
        if(b<0) a=-a, b=-b;
    }
    Frac(ll a): a(a){
        b=0;
    }

    Frac operator-(const Frac &r)const{
        ll g = __gcd(b, r.b);
        return Frac(a*(r.b/g)-r.a*(b/g), b/g*r.b);
    }

    Frac operator*(const Frac &r)const{
        return Frac(a*r.a, b*r.b);
    }

    bool operator<(const Frac &r)const{
        return a*r.b < b*r.a;
    }

    bool operator<=(const Frac &r)const{
        return a*r.b < b*r.a;
    }

    bool operator>(const Frac &r)const{
        return a*r.b > b*r.a;
    }

    bool operator==(const Frac &r)const{
        return a*r.b == b*r.a;
    }
};

struct vector2{
    Frac x, y;
    vector2(){}
    vector2(Frac x, Frac y): x(x), y(y){}

    vector2 operator-(const vector2 r)const{
        return vector2(x-r.x, y-r.y);
    }

    bool operator<(const vector2 &r)const{
        return make_pair(x, y) < make_pair(r.x, r.y);
    }

    bool operator==(const vector2 &r)const{
        return x==r.x && y==r.y;
    }

    Frac cross(vector2 r)const{
        return x*r.y - y*r.x;
    }
};

Frac ccw(vector2 a, vector2 b){
    return a.cross(b);
}

Frac ccw(vector2 a, vector2 b, vector2 c){
    return (b-a).cross(c-a);
}

vector2 point;
int n;
vector2 arr[100002];
bool deleted[100002];
int arrSize;

void input(vector2 &p){
    int a, b, c;
    scanf("%d %d %d", &a, &b, &c);
    p.x = Frac(a, a+b+c);
    p.y = Frac(b, a+b+c);
}

vector<vector2> hull(vector<vector2> &vec){
    vector<vector2> ret;
    sort(vec.begin(), vec.end());
    sort(vec.begin()+1, vec.end(), [&](vector2 A, vector2 B){
        return ccw(A, vec[0], B) < 0;
    });
    ret.push_back(vec[0]);
    for(int i=1; i<(int)vec.size(); i++){
        while(ret.size()>=2 && ccw(ret[ret.size()-2], ret.back(), vec[i]) <= 0) ret.pop_back();
        ret.push_back(vec[i]);
    }
    return ret;
}

inline int sign(Frac x){
    if(x>0) return 1;
    if(x<0) return -1;
    return 0;
}

bool inside(vector<vector2> &vec, vector2 p){
    if((int)vec.size() <= 2) return 0;
    int s = sign(ccw(vec.back(), vec[0], p));
    for(int i=0; i<(int)vec.size()-1; i++){
        if(s != sign(ccw(vec[i], vec[i+1], p))) return false;
    }
    return true;
}

void calc(){
    vector<vector2> vec;
    for(int i=1; i<=arrSize; i++){
        if(!deleted[i]){
            if(arr[i] == point){
                puts("1");
                return;
            }
            vec.push_back(arr[i]);
        }
    }
    if(vec.empty()){
        puts("0");
        return;
    }
    for(int i=0; i<(int)vec.size(); i++){
        for(int j=i+1; j<(int)vec.size(); j++){
            if(ccw(vec[i], vec[j], point) == 0 && (vec[i] < point) ^ (vec[j] < point)){
                puts("2");
                return;
            }
        }
    }
    vec = hull(vec);
    if(inside(vec, point)) puts("3");
    else puts("0");
}

int main(){
    input(point);
    scanf("%d", &n);
    for(int i=1; i<=n; i++){
        char c;
        scanf(" %c", &c);
        if(c == 'A') input(arr[++arrSize]);
        else{
            int x;
            scanf("%d", &x);
            deleted[x] = 1;
        }
        calc();
    }
}

Compilation message

Mixture.cpp: In function 'void input(vector2&)':
Mixture.cpp:83:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   83 |     scanf("%d %d %d", &a, &b, &c);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
Mixture.cpp: In function 'int main()':
Mixture.cpp:147:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  147 |     scanf("%d", &n);
      |     ~~~~~^~~~~~~~~~
Mixture.cpp:150:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  150 |         scanf(" %c", &c);
      |         ~~~~~^~~~~~~~~~~
Mixture.cpp:154:18: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  154 |             scanf("%d", &x);
      |             ~~~~~^~~~~~~~~~

Subtask #1
0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 260 KB Output is correct
2 Incorrect 1 ms 304 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #2
0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 260 KB Output is correct
2 Incorrect 1 ms 304 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #3
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 260 KB Output is correct
2 Incorrect 1 ms 304 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #4
0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 260 KB Output is correct
2 Incorrect 1 ms 304 KB Output isn't correct
3 Halted 0 ms 0 KB -