vector<int>::iterator result = find( L.begin( ), L.end( ), 3 ); //查找3 if ( result == L.end( ) ) //没找到 cout << "No" << endl; else //找到 cout << "Yes" << endl; } 记着要包含algorithm这一头文件,其定义了find这一函数。 资料参考:https://www.coonote.com/cplusplus-note/vector-find.html
vector<int>vec; vec.push_back(123); vec.push_back(456); vector<int>::iterator findit=find(vec.begin(),vec.end(),123); //vector<int>::iterator findit = find(vec.begin(),vec.end(),111); if(findit==vec.end()) { printf("no find\n"); } else { printf("find[%d]\n",*fi...
cpp 运行 #include<vector>#include<algorithm> std::vector<int>vec={3,1,4,1,5,9};autoit=std::find(vec.begin(),vec.end(),5);// O(n) 时间复杂度 如果需要频繁查找元素,且元素具有可排序的特性,可以通过以下方式优化:将vector排序后使用std::binary_search或std::lower_bound,时间复杂度可降...
In this program, a vector is declared with no elements, and on executing the code, the size of the vector will be displayed as 0. Example #5 CPP program that declares a vector add elements and print size Code: #include <iostream> #include <vector> using namespace std; //main method ...
in the vector that contain at least one digitstd::vector<std::string>test(std::vector<std::string>colors){std::vector<std::string>result;// Creating a new vector to store strings containing digits// Loop through each string in the input vector 'colors'for(auto&text:colors){autoit=std:...
STL_string.vector中find到的iterator的序号 ZC:注意,printf("0x%08X\n",vtr.end()); 打印出来 应该就是 0x00000000,∵ 它就是 指向最后一个元素的后面,应该是理解成 无意义 值是0 很合理。 1、测试代码(以及 我的疑问) /*ZC: 网上查到,使用vector时,只要将 find到的iterator(itX)减去vector::begin()...
// [[Rcpp::export(rng = false)]] Eigen::SparseMatrix<double> ComputeSNN(Eigen::MatrixXd nn_ranked, double prune) { std::vector<T> tripletList; //声明一个向量 int k = nn_ranked.cols(); //总列数 tripletList.reserve(nn_ranked.rows() * nn_ranked.cols()); //定义行列,初始化全0...
Display_a_map.cpp Display_a_map::Display_a_map(QObject* parent /* = nullptr */): QObject(parent), m_map(new Map(BasemapStyle::ArcGISStreets, this)), m_currentState(RouteBuilderStatus::NotStarted) Call the setupRouteTask() method within the constructor. This will be populated in a ...
std::vector<int>v={2,1,3,6,7,9,8}; intmin=findMinimum(v); intmax=findMaximum(v); std::cout<<min<<", "<<max<<std::endl;// 1, 9 return0; } DownloadRun Code That’s all about finding the min or max value in a vector in C++. ...
This post will discuss how to find the index of the first occurrence of a given element in vector in C++. 1. Using std::find with std::distance function The simplest solution is to use the std::find algorithm defined in the <algorithm> header. The idea is to get the index using std...