[3] 숫자 게임

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

using namespace std;

int solution(vector<int> A, vector<int> B) 
{
    int answer = 0;
    sort(A.begin(),A.end());
    sort(B.begin(),B.end());
    
    int idxA=A.size()-1,idxB=B.size()-1;
    
    while(idxA >= 0)
    {
        int valA=A[idxA],valB=B[idxB];
        
        if(valB > valA)
        {
            answer++;
            idxB--;
        }
        idxA--;
    }
    return answer;
}