Submission #552108

# Submission time Handle Problem Language Result Execution time Memory
552108 2022-04-22T12:33:36 Z patrikpavic2 SIR (COI15_sir) C++17
61 / 100
225 ms 21156 KB
#include <cstdio>
#include <cstdlib>
#include <algorithm>
#include <vector>
#include <set>
#include <map>
#include <cmath>
 
#define mp make_pair
#define X first
#define Y second
 
using namespace std;
 
typedef long long llint;
typedef pair < llint,llint> pii;
 
const llint N = 1e5 + 500;
const llint INF = 0x3f3f3f3f;
const llint MOD = 1e9 + 7;
vector < pii > hull;
vector < pii > v2;
vector < pii > hull2;
pii P;
llint n,m,nn;
 
llint ccw(pii A,pii B,pii C){
    return A.X * (B.Y - C.Y) + B.X * (C.Y - A.Y) + C.X * (A.Y - B.Y);
}
 
llint dis(pii A,pii B){
    return (A.X - B.X) * (A.X - B.X) + (A.Y - B.Y) * (A.Y - B.Y);
}
 
bool cmp(pii A,pii B){
    if(ccw(A,B,P) == 0) return dis(A,P) < dis(B,P);
    return ccw(P,A,B) > 0;
}
bool cmpa(pii a, pii b) {
    if(a.second != b.second) return a.second < b.second;
    return a.first < b.first;
}
 
void convex_hull(){
    sort(v2.begin(),v2.end());
    P = v2[0];
    sort(v2.begin() + 1,v2.end(),cmp);
    hull2.push_back(P);
    for(int i = 1;i<v2.size();i++){
        while(hull2.size() >= 2 && ccw(hull2[hull2.size()-2],hull2[hull2.size()-1],v2[i]) <= 0){
            hull2.pop_back();
        }
        hull2.push_back(v2[i]);
    }
    nn = hull2.size();
}
 
llint solve(){
    llint sol = 0;
    llint cur = 0;
    int j = 0,k = 0;
    for(int i = 0;i<n;i++){
        while(ccw(hull[i],hull2[k],hull2[(k+1)%nn]) < 0){
            k=(k+1)%nn;
        }
        while(ccw(hull[i],hull[j],hull2[k]) > 0 || i == j){
            cur += ccw(hull[i],hull[(j-1+n)%n],hull[j]);
            j=(j+1)%n;
        }
        sol = max(sol, cur);
        cur -= ccw(hull[i],hull[(i+1)%n],hull[(j-1+n)%n]);
 
    }
    return sol;
}
 
void load(){
    scanf("%lld",&n);
    for(llint i = 0;i<n;i++){
        llint x,y;scanf("%lld%lld",&x,&y);
        hull.push_back(make_pair(x,y));
    }
    scanf("%lld",&m);
    for(llint i = 0;i<m;i++){
        llint x,y;scanf("%lld%lld",&x,&y);
        v2.push_back(make_pair(x,y));
    }
}
 
int main(){
    load();
    convex_hull();
    printf("%lld\n",solve());
}

Compilation message

sir.cpp: In function 'void convex_hull()':
sir.cpp:49:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   49 |     for(int i = 1;i<v2.size();i++){
      |                   ~^~~~~~~~~~
sir.cpp: In function 'void load()':
sir.cpp:78:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   78 |     scanf("%lld",&n);
      |     ~~~~~^~~~~~~~~~~
sir.cpp:80:24: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   80 |         llint x,y;scanf("%lld%lld",&x,&y);
      |                   ~~~~~^~~~~~~~~~~~~~~~~~
sir.cpp:83:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   83 |     scanf("%lld",&m);
      |     ~~~~~^~~~~~~~~~~
sir.cpp:85:24: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   85 |         llint x,y;scanf("%lld%lld",&x,&y);
      |                   ~~~~~^~~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 1 ms 292 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 2 ms 340 KB Output is correct
2 Correct 1 ms 396 KB Output is correct
3 Correct 3 ms 488 KB Output is correct
4 Correct 1 ms 468 KB Output is correct
5 Incorrect 2 ms 468 KB Output isn't correct
6 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 206 ms 21156 KB Output is correct
2 Correct 225 ms 20060 KB Output is correct
3 Correct 155 ms 20780 KB Output is correct
4 Correct 39 ms 7300 KB Output is correct
5 Correct 192 ms 17520 KB Output is correct
6 Correct 148 ms 17964 KB Output is correct