C++地图模板不会插入

我正在使用一个名为 ITV 的映射模板，其中定义的结构作为键值，一组整数对作为映射值。出于任何原因，插入命令根本不适用于某些键值。

我已经将代码减少到尽可能小，但它仍然很大。它可以编译和执行，每当将一对添加到某个域的映射值时返回一行，指示当时键值和关联映射值的大小。

不幸的是，在函数intervals()的某个点(在初始弧的情况下(，插入命令什么都不做：

ITV[Domain(PairStr,q)].insert(make_pair(t,t)); // ERROR! DOES NOT WORK

我想这可能与map类的某些内部排序有关，因为只有在("INI", "A")PairStr时才会发生错误，这是PairStr.first > PairStr.second的唯一情况，但我真的对此一无所知。

#include <iostream>
#include <vector>
#include <map>
#include <iterator>
#include <string>
#include <set>
using namespace std;
typedef set<pair<string,string> > SPS;
typedef set<pair<string,string> >::iterator SPSIt;
struct Domain {
string i;
string j;
int q;
Domain() : i("NaNode"), j("NaNode"), q(-1) {}
Domain(string oi, string oj, int oq) : i(oi), j(oj), q(oq) {}
Domain(pair<string,string> ops, int oq) : i(ops.first), j(ops.second), q(oq) {} 
bool operator< (Domain const &domain) const {
return i < domain.i || j < domain.j || q < domain.q;
}
};
// GRAPH STRUCTURE
SPS ARCS, INIT_ARCS, DEST_ARCS, TOTAL_ARCS;
map<Domain ,set<pair<int,int> > > ITV;
// TIME and SO ON
int T_MAX, Q_MAX; // number of periods and stages
vector<int> STG_first; // first and last period of stage q
vector<int> STG_last;
void intervals(){
pair<string,string> PairStr; // auxiliar variable
// loop for generating intervals
for(SPSIt it = TOTAL_ARCS.begin(); it != TOTAL_ARCS.end(); ++it)
for(int q = 0; q < Q_MAX; ++q)
for(int t = STG_first[q]; t<= STG_last[q]; ++t){
PairStr = *it;
// Case regular arc
if (ARCS.count(PairStr)){
for(int v = t; v <= STG_last[q]; ++v){
ITV[Domain(PairStr,q)].insert(make_pair(t,v));
cout << "Size of " << PairStr.first << "-" << PairStr.second << " at " << q << ": " << ITV[Domain(PairStr,q)].size() << endl;
}
// Case initial arc
} else if (INIT_ARCS.count(PairStr)){
ITV[Domain(PairStr,q)].insert(make_pair(t,t)); // ERROR! DOES NOT WORK
cout << "Size of " << PairStr.first << "-" << PairStr.second << " at " << q << ": " << ITV[Domain(PairStr,q)].size() << endl;
// Case destination arc
} else if (DEST_ARCS.count(PairStr) && q > 0){
ITV[Domain(PairStr,q)].insert(make_pair(t,t));
cout << "Size of " << PairStr.first << "-" << PairStr.second << " at " << q << ": " << ITV[Domain(PairStr,q)].size() << endl;
}
}// end loop
}// end intervals()
int main (){
// read arcs
ARCS.insert(make_pair("A", "B"));
TOTAL_ARCS.insert(make_pair("A", "B"));
INIT_ARCS.insert( make_pair("INI", "A"));
TOTAL_ARCS.insert(make_pair("INI", "A"));
DEST_ARCS.insert( make_pair("B", "DES"));
TOTAL_ARCS.insert(make_pair("B", "DES"));
// read number of periods and stages
T_MAX = 3;
Q_MAX = 2;
STG_first = vector<int> (Q_MAX);
STG_last  = vector<int> (Q_MAX); 
STG_first[0] = STG_last[0] = 0;
STG_first[1] = 1;
STG_last[1] = 2;
intervals();
return 0;
}   // END main

所需的输出如下：

Size of A-B at 0: 1
Size of A-B at 1: 1
Size of A-B at 1: 2
Size of A-B at 1: 3
Size of B-DES at 1: 1
Size of B-DES at 1: 2
Size of INI-A at 0: 1
Size of INI-A at 1: 1
Size of INI-A at 1: 2

但目前的输出是这样的：

Size of A-B at 0: 1
Size of A-B at 1: 1
Size of A-B at 1: 2
Size of A-B at 1: 3
Size of B-DES at 1: 1
Size of B-DES at 1: 2
Size of INI-A at 0: 0
Size of INI-A at 1: 0
Size of INI-A at 1: 0

很抱歉这篇文章很长，我将不胜感激对此的任何提示。