map<char,string>testmap; testmap['a']="c/c++"; testmap['b']="java"; testmap['c']="php"; testmap['d']="python"; testmap['e']="golang";//使用begin()正序遍历map<char,string>::iterator it;for(it=testmap.begin();it!=testmap.end();it++) cout<<it->first<<"-> "<<it...
//c mapStu.insert(pair<int, string>(1, "stu1")); mapStu.insert(pair<int, string>(2, "stu2")); mapStu.insert(pair<int, string>(3, "stu3")); map<int, string>::iterator inter; for (inter = mapStu.begin(); inter != mapStu.end(); inter++) cout << inter->first << en...
map<string, int> word_count; word_count["Hello"] = 3; word_count["World"] = 3; //map_it为map<string, int>::const_iterator类型 auto map_it = word_count.cbegin(); while (map_it != word_count.cend()) { cout << map_it->first << "" << map_it->second << endl; ++map_...
" [a 1] [b 2] [c 3]" for each (Mymap::value_type elem in c1) System::Console::Write("[{0} {1}] ", elem->first, elem->second); System::Console::WriteLine(); // compute positive difference Mymap::difference_type diff = 0; for (Mymap::iterator it = c1.begin(); it ...
map<int, int>::iterator it; for (it = mp.begin(); it != mp.end(); it++){ printf("%d->%d\n", it->first, it->second); } return 0; } 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17.
遍历map需要用到std::iterator迭代器,没有接触过的同学可能不太了解,可以先看代码,或者用第二种方法。 方法一:迭代器法 代码语言:c++ 复制 void print(map<int, string> mp) { cout << '{'; for(map<int, string>::iterator it = mp.begin(); it != mp.end(); ++ it) ...
那么问题来了it=map.erase(it),然后对it进行操作会发生什么呢?会发生传说中的“未定义的行为”!包括但不限于程序挂掉、机器死机、地球地震、宇宙毁灭等–原因是什么呢?在执行map.erase(it)之后,it这个iterator已经失效了,考虑C语言中一个失效释放了的指针,再次引用它会导致什么问题呢?
#include<map>#include<iostream>usingnamespacestd;intmain(){map<char,int>maps;maps['d']=10;maps['e']=20;maps['a']=30;maps['b']=40;maps['c']=50;maps['r']=60;for(map<char,int>::iteratorit=mp.begin();it!=mp.end();it++){cout<<it->first<<" "<<it->second<<endl;}ret...
C++中map遍历有两种方法: 第一种,使用迭代器,while循环 代码语言:javascript 复制 #include<iostream>#include<map>using namespace std;intmain(){map<int,int>p;p[0]=1;p[1]=2;p[3]=4;map<int,int>::iterator it=p.begin();while(it!=p.end()){cout<<it->first<<" "<<it->second<<endl...
void printMap(map<int, int>& m) { for (map<int,int>::iterator it ...