[Solved] How to erase elements in STL vector without copying iterator and without memory leakage?

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You dont need to worry about memory leaks, in your case you use std::vector which uses RAII to make sure no memory is leaked. With STL containers you can “leak” in such case on;y if you do not shrink your vector after using remove algorithm.

Below is fix to your code, and not entire rewrite. This code removes all values equal to 1 [LIVE]:

vector<vector<int> > vec = { {0,1,2,3}, {0,1,2,3,4,5}, {0,1} }; 
vector<vector<int> >::iterator vit = vec.begin(); 
vector<int>::iterator it;

while(vit != vec.end()) {
    it = vit->begin();
    while(it != vit->end()) {
     if( *it == 1 ) {
        it = vit->erase(it);

         // Not sure why you want this loop here
         //while( condition )
         //{
         //     **erase an element;**
         //}
     }
     else {
       ++it;
     }
    }
    ++vit;
}  

for (auto it1 = vec.begin(); it1 != vec.end(); ++it1){
    for (auto it2 = it1->begin(); it2 != it1->end(); ++it2)
       std::cout<<*it2<< ", ";
    std::cout << "\n";
}

produces:

g++ -std=c++14 -O2 -Wall -pedantic -pthread main.cpp && ./a.out
0, 2, 3, 
0, 2, 3, 4, 5, 
0,

3

solved How to erase elements in STL vector without copying iterator and without memory leakage?