列出迭代器作为访问和修改std：list内容的方法

Question

说你有名单

NTlist （这里抽象地表示）：

     ["string2", RHSlist ]<-->["string1", RHSlist ]<-->["string3", RHSlist ]

现在，您搜索包含＆＃34; string1＆＃34;的NTlist元素。使用列表迭代器， NTlocation 。搜索结果为NTlocation然后＆＃34;点＆＃34;到中间的元素。

目标是添加到此中间元素的RHS列表中。我这样做：

 NTlocation->RHSlist.push_back(RHSentry); //where RHSentry is of type RHSnode. 

问题：
为什么中间元素的RHS列表没有更新？相反，迭代器NTlocation具有更新的RHS列表。

感谢您的时间。

#include <list>
#include <iostream>
#include <string.h>
using namespace std;

typedef struct RHSnode {
string token;
} RHSnode;

typedef struct NTnode {
string token;
list<RHSnode> RHSlist;
} NTnode;

list<NTnode>::iterator searchNTList(string NTstring, list<NTnode> &NTlist);

int main(int argc, const char * argv[]) {
 list<NTnode> NTlist;
 list<NTnode>::iterator NTlocation;

// making three entries in NTList
NTnode entry1;
entry1.token = "string2";
NTlist.push_back(entry1);

NTnode entry2;
entry2.token = "string1";
NTlist.push_back(entry2);

NTnode entry3;
entry3.token = "string3";
NTlist.push_back(entry3);

RHSnode RHSentry;
RHSentry.token = "RHSentry";

//Now, say, I want to put this RHSentry (above) into NTlist with
// element that has it's token as "string1"
// so I search NTlist for token with "string1"
// and remember the NTlist element location with iterator NTlocation
 NTlocation = searchNTList("string1", NTlist);

// Now here's where the problem occurs
 NTlocation->RHSlist.push_back(RHSentry);

return 0;
}

list<NTnode>::iterator searchNTList(string NTstring, list<NTnode> &NTlist){
//"past-the-end" indications search failure
list<NTnode>::iterator NTlocation = NTlist.end();

list<NTnode>::iterator iterator = NTlist.begin();

for ( ; iterator != NTlist.end() ; iterator++ ){

    if (iterator->token.compare(NTstring) == 0){
        NTlocation = iterator;
        break;
    }

}
 return NTlocation;
}