matrix filling, but it is skipping an element each row, why? [closed] - c++

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I have these vectors as follows
vector< vector< Arc * > * > _adjacences;
vector <int> list[_adjacences.size()];
vector <int> listD[_adjacences.size()];
vector < vector <int> > matrix( _adjacences.size(), vector<int>(_adjacences.size(),0 ));
vector < vector <int> > shortPath( _adjacences.size(), vector<int>(_adjacences.size(),0 ));
I want to make the adjacency list to an adjacency matrix
Arc contains these:
int sommetArrive;
int longueur;
string nom;
I tried to make two vectors one for the distance and the other for the peeks
for (unsigned i = 0; i < _adjacences.size(); i++){
for (auto j : *_adjacences[i]){
list[i].push_back(j->sommetArrive);
listD[i].push_back(j->longueur);
}
}
Then I make the adjacency matrix, THIS IS WHERE I'M DOING THINGS WRONG
for (int i = 0; i < _adjacences.size(); i++) {
for (auto j : list[i]){
for (auto k : listD[i]){
matrix[i][j] = k;
}
}
}
Instead of getting this:
0 0 0 0 0 0 0 0 0 0 0 0 0 120 0 62
0 0 253 0 0 0 0 0 0 0 204 0 0 0 0 0
0 53 0 12 0 0 105 0 0 0 0 0 0 0 0 0
0 0 15 0 38 0 0 108 0 0 0 0 0 0 0 0
0 0 0 93 0 123 0 0 113 0 0 0 0 0 0 0
0 0 0 0 158 0 0 0 0 118 0 0 0 0 0 0
0 0 97 0 0 0 0 17 0 0 0 87 0 0 0 0
0 0 0 103 0 0 3 0 53 0 0 0 73 0 0 0
0 0 0 0 153 0 0 33 0 113 0 0 0 0 0 0
0 0 0 0 0 55 0 0 91 0 0 0 0 72 0 0
I end up with this
0 0 0 0 0 0 0 0 0 0 0 0 0 62 0 62
0 0 204 0 0 0 0 0 0 0 204 0 0 0 0 0
0 105 0 105 0 0 105 0 0 0 0 0 0 0 0 0
0 0 108 0 108 0 0 108 0 0 0 0 0 0 0 0
0 0 0 113 0 113 0 0 113 0 0 0 0 0 0 0
0 0 0 0 118 0 0 0 0 118 0 0 0 0 0 0
0 0 87 0 0 0 0 87 0 0 0 87 0 0 0 0
0 0 0 73 0 0 73 0 73 0 0 0 73 0 0 0
0 0 0 0 113 0 0 113 0 113 0 0 0 0 0 0
0 0 0 0 0 72 0 0 72 0 0 0 0 72 0 0
Where the same number is being repeated instead of passing to the next element k
What did I do wrong ?

Answer 1

Notice that for every i you use the same list listD[i]. The inner loop:
for (auto k : listD[i]){
matrix[i][j] = k;
}
will assign all values in listD[i], one by one, to matrix[i][j], until the final value remains. This is the same as writing matrix[i][j] = listD[i].back().
You probably need to replace the inner loop with matrix[i][j] = listD[i][j].