#include<bits/stdc++.h>
using namespace std;
int main() {
int b, n, cb = 0;
cin >> b >> n;
vector<int> t;
vector<int> cs = {b};
for (int i = 0; i < n; i++) {
string placementlelo;
cin >> placementlelo;
if (placementlelo == "read") {
cout << cs[cb] << endl;
}
else if (placementlelo == "credit" || placementlelo == "debit") {
int x;
cin >> x;
if (placementlelo == "credit") cs[cb] += x;
else cs[cb] -= x;
t.push_back(placementlelo == "credit" ? x : -x);
}
else if (placementlelo == "abort") {
int x;
cin >> x;
if (x <= t.size()) cs[cb] -= t[x - 1], t[x - 1] = 0;
}
else if (placementlelo == "rollback") {
int x;
cin >> x;
cb = x - 1;
cs.resize(cb + 1);
}
else if (placementlelo == "commit") {
cs.push_back(cs[cb]);
cb++;
}
}
return 0;
}