<p>A transaction is possibly invalid if:</p>

<ul>
	<li>the amount exceeds <code>$1000</code>, or;</li>
	<li>if it occurs within (and including) <code>60</code> minutes of another transaction with the <strong>same name</strong> in a <strong>different city</strong>.</li>
</ul>

<p>You are given an array of strings <code>transaction</code> where <code>transactions[i]</code> consists of comma-separated values representing the name, time (in minutes), amount, and city of the transaction.</p>

<p>Return a list of <code>transactions</code> that are possibly invalid. You may return the answer in <strong>any order</strong>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> transactions = [&quot;alice,20,800,mtv&quot;,&quot;alice,50,100,beijing&quot;]
<strong>Output:</strong> [&quot;alice,20,800,mtv&quot;,&quot;alice,50,100,beijing&quot;]
<strong>Explanation:</strong> The first transaction is invalid because the second transaction occurs within a difference of 60 minutes, have the same name and is in a different city. Similarly the second one is invalid too.</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> transactions = [&quot;alice,20,800,mtv&quot;,&quot;alice,50,1200,mtv&quot;]
<strong>Output:</strong> [&quot;alice,50,1200,mtv&quot;]
</pre>

<p><strong class="example">Example 3:</strong></p>

<pre>
<strong>Input:</strong> transactions = [&quot;alice,20,800,mtv&quot;,&quot;bob,50,1200,mtv&quot;]
<strong>Output:</strong> [&quot;bob,50,1200,mtv&quot;]
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>transactions.length &lt;= 1000</code></li>
	<li>Each <code>transactions[i]</code> takes the form <code>&quot;{name},{time},{amount},{city}&quot;</code></li>
	<li>Each <code>{name}</code> and <code>{city}</code> consist of lowercase English letters, and have lengths between <code>1</code> and <code>10</code>.</li>
	<li>Each <code>{time}</code> consist of digits, and represent an integer between <code>0</code> and <code>1000</code>.</li>
	<li>Each <code>{amount}</code> consist of digits, and represent an integer between <code>0</code> and <code>2000</code>.</li>
</ul>

class Solution {
public:
    vector<string> invalidTransactions(vector<string>& transactions) {
        unordered_set<int> invalid;
        vector<vector<string>> trans;
        for (int i = 0; i < transactions.size(); i++) {
            int l = 0, r = 0;
            vector<string> temp;
            for (; r < transactions[i].size(); r++) {
                if (transactions[i][r] == ',') {
                    temp.push_back(transactions[i].substr(l, r - l));
                    l = r + 1;
                }
            }
            temp.push_back(transactions[i].substr(l, r - l));

            trans.push_back(temp);
        }

        map<string, vector<pair<int, int>>> transm;
        for (int i = 0; i < trans.size(); i++) {
            if (stoi(trans[i][2]) > 1000)
                invalid.insert(i);
            // else {
                transm[trans[i][0]].push_back({stoi(trans[i][1]), i});
            // }
        }

        for (auto& i : transm) {
            sort(i.second.begin(), i.second.end());
            // int l = 0, r = 0;
            // while (r < i.second.size()) {
            for(int j=0;j<i.second.size();j++){
                for(int k=j+1;k<i.second.size();k++){
                if (abs(i.second[j].first - i.second[k].first) <= 60) {

                    if (trans[i.second[j].second][3] != trans[i.second[k].second][3]) {
                        invalid.insert(i.second[j].second);
                        invalid.insert(i.second[k].second);
                    } 
                        // r++;
                }else
                        // l++;
                        break;
                }
            }
        }
        vector<string>ans;
        for(auto&i:invalid) ans.push_back(transactions[i]);
        return ans;
    }
};
20500