[프로그래머스 C++] 단속카메라

[프로그래머스 C++ : 단속카메라]

 

#include <string>
#include <vector>
#include <algorithm>

using namespace std;

int solution(vector<vector<int>> routes) {
    int answer = 0;
    
    ::sort(routes.begin(), routes.end(), [](const vector<int>& A, const vector<int>& B) { return A[1] < B[1]; });
    // [-20, -15], [-18, -13], [-14, -5], [-5, -3]
    
    int cnt = 0;
    int last = -30'001;
    for (int i=0; i<routes.size(); i++)
    {
        const int start = routes[i][0];
        const int end = routes[i][1];
        if (last < start)
        {
            cnt++;
            last = end;
        }
    }
    
    return answer = cnt;
}