c++如何用stl二分查找一个装有有序数组的vector中,比某个数小的最大数...答:include<iostream>#include<algorithm>#include<vector>using namespace std;int main(){int sou=4;//题目中的某个数。vector<int> x({3,4,5,6,7,11,12,13});//题目中有序数组的vectorauto it=lower_bound(x.begin(), x.end(), sou);if(it!=x.begin()) cout<<*--it;else cout...