vector function implement the greedy algorithm but answer have some wrong, some result can't print out

Please refer the figure and modify the code. My answer have some wrong, some parcel will disappear. Please help to make some modification.

SAMPLE INPUT:

• Maximum amount of weight a truck is allowed to carry
• parcel arriving at trucking station(in sequence)
• weight of each parcel arriving at the loading station

SAMPLE OUTPUT:

• trucks leaving the station(in sequence) and the corresponding parcels and weight that has been loaded into the truck
• parcels that could not be loaded into the truck and the corresponding weight of the parcel.

cout <<"---------------------------------------------------------------" <<endl;
cout <<"Enter Maximum Amount of weight(KG) a truck is allowed to carry." << endl;
cout <<"Maximum Amount: ";
cin>>WT; //the maximum amount of weight
cout <<"Enter the number of parcels wants to ship." << endl;
cout <<"Number of parcels:";
cin>>num_parcel; //total number of parcels

vector<int>parcel_weight(num_parcel,0); //create the vector weight of parcel array
for(int i=0;i<num_parcel;i++) //input weight of开发者_StackOverflow社区 every parcel
{
    cout << "No." << i+1 << " Parcel weight: ";
    cin>>parcel_weight[i];
}

vector<vector<pair<int,int>>>truck(5,vector<pair<int,int>>()); //create 5 truck array & put the parcel weight
vector<pair<int,int>> unloaded_parcel; //unloaded parcel vector array
int truck_No=0;
int total_weight_truck=0;

for(int i=0;i<num_parcel;i++) //check the parcel and separately the parcel to relative array.
{
    if(parcel_weight[i]>WT || truck_No>=5) //if parcel can't loaded
    {
        unloaded_parcel.push_back(make_pair(i,parcel_weight[i]));//put parcel to unloaded_parcel array, if exceed truck can carry weight.
    }
    else if(parcel_weight[i]> WT-total_weight_truck)  //if parcel exceed the truck weight, move to the next truck.
    {
        total_weight_truck=0; //new truck
        truck_No++;
    }
    else //parcel load
    {
        total_weight_truck= total_weight_truck+parcel_weight[i];
        truck[truck_No].push_back(make_pair(i,parcel_weight[i]));
    }
}

for(int i=0;i<5;i++) //print out the 5 truck information which include the parcel
{
    cout<< "Truck " << i+1 << " included:" << endl;
    for(int j=0;j<truck[i].size();j++)
    {
        cout<<"Parcel No." << truck[i][j].first+1 <<" and parcel weight is " <<truck[i][j].second<< "KG" <<endl;
    }
    cout<<endl;
}

cout<<"Parcel can't loaded in truck is:" << endl; //print out the parcel that can't load
for(int i=0;i<unloaded_parcel.size();i++)
{
    cout<<"Parcel No."<<unloaded_parcel[i].first+1<< " and parcel weight is "<<unloaded_parcel[i].second<< "KG" <<endl;
}

Here is my complier answer