C++ push_back overwrites last vector element - c++

Question

Since I cannot answer my own question in 8 hours after asking, I'm posting my solution here.
Made some mistakes in the incoming channel number and number of the vector element. Setting the value of channel-1 instead of channel fixed to problem.
My new function is as follows:
void input(long inlet, t_symbol *s, long ac, t_atom *av){
// GET VARIABLES
long channel = atom_getlong(av);
double value = atom_getfloat(av + 1);
long v_size = v_chan.size();
if(channel && v_size < channel){
for(int i = v_size; i < channel; i++){
v_chan.push_back(n_chan);
}
v_chan[channel - 1].value = value;
}
else if(channel){
v_chan[channel - 1].value = value;
}
}
I've got a vector containing structs, which I like to push_back with a new, empty struct.
Example code:
struct channels{
double value;
// eventually more variables
};
vector<channels> v_chan;
channels n_chan;
void push(){
v_chan.push_back(n_chan);
}
The problem is, if my vector contains elements, push_back add an element, but also overwrites the last element.
For example, if my vector size is 1 and element 0 has a value of 0.2, after push_back my vector size is 2, but element 0 and 1 have a value of 0.
What am I doing wrong here?
Real Code: (MAX/MSP external, function input is called in Max)
#include <maxcpp6.h>
#include <string>
#include <algorithm>
#include <vector>
using namespace std;
struct bind{
string param;
double* value;
int track;
double base;
double multiplier;
};
struct channels{
double value;
vector<int> bind;
};
vector<channels> v_chan;
vector<bind> v_bind(19);
channels n_chan;
class rec : public MaxCpp6<rec> {
public:
rec(t_symbol * sym, long ac, t_atom * av) {
setupIO(1, 1); // inlets / outlets
}
~rec() {}
// methods:
//SET BIND FUNCTION
void setBind(long inlet, t_symbol *s, long ac, t_atom *av){
}
void output(long track, long type){
}
void input(long inlet, t_symbol *s, long ac, t_atom *av){
// GET VARIABLES
long channel = atom_getlong(av);
double value = atom_getfloat(av + 1);
long v_size = v_chan.size();
if(v_size <= channel){
v_chan.push_back(n_chan);
}
else{
v_chan[channel].value = value;
}
}
void dump(long inlet){
for(int i = 1; i <= v_chan.size(); i++){
post("%d %.2f", i, v_chan[i].value);
}
}
void clearTrackBinds(long inlet){
}
void reset(long inlet){
clearTrackBinds(0);
}
};
C74_EXPORT int main(void) {
// create a class with the given name:
rec::makeMaxClass("solar_receiver");
REGISTER_METHOD_GIMME(rec, input);
REGISTER_METHOD_GIMME(rec, setBind);
REGISTER_METHOD(rec, dump);
REGISTER_METHOD(rec, clearTrackBinds);
REGISTER_METHOD(rec, reset);
}