#include <bits/stdc++.h>
using namespace std;
int f(string str, int n){
stack<char> s;
int count = 0;
int i = 1;
s.push(str[0]);
while (true){
if (i == n) break;
if (str[i] == s.top()) s.push(str[i++]);
else if (str[i] != s.top()){
if (s.top() == '0'){
while (!s.empty() && s.top() == '0') s.pop();
if (!s.empty() && s.top() != str[i]){
s.push('0');
s.push(str[i++]);
}
else s.push(str[i++]);
}
else if (s.top() == '+' && str[i] == '0'){
while (i < n && str[i] == '0') i++;
if (i == n) continue;
if (s.top() != str[i]){
s.push('0');
s.push(str[i++]);
}
else s.push(str[i++]);
}
else if (s.top() == '-' && str[i] == '0'){
while (i < n && str[i] == '0') i++;
if (i == n) continue;
if (s.top() != str[i]){
s.push('0');
s.push(str[i++]);
}
else s.push(str[i++]);
}
else {
if (i == n) continue;
s.push(str[i++]);
}
}
}
while (!s.empty()){
if (s.top() == '0') count++;
s.pop();
}
return count;
}
int main() {
// your code goes here
int t;
cin >> t;
while (t--){
int n;
cin >> n;
string s;
cin >> s;
cout << f(s, n) << endl;
}
return 0;
}
Can anyone help me figure out testcases on which above code fails.
