Create day004sol01.cpp

Author: Naman2251

Problems/Data-structures/Day-04/sol/Naman Pal/day004sol01.cpp

@@ -0,0 +1,45 @@
+// Submission Link: https://codeforces.com/contest/1997/submission/355835686
+
+
+/*
+So first I made the RBS with minimmum cost by putting closing bracket as soon as we get a opening bracket before it, i.e., closing bracket as early as 
+possible(greedy appraoch). After getting corect bracket sequence I put the indexes of '(' in vector o and indexes of ')' in vector c in order they occur. Both 
+vector must contain n/2 elements and now for final answer I simply added the difference of each element in o and c at same index to ans to calculate cost 
+which was initially zero and then printed the ans.
+*/
+#include <bits/stdc++.h>
+using namespace std;
+
+int main() {
+    long long t;
+    cin>>t;
+    while(t--) {
+        long long n;
+        cin>>n;
+        string s;
+        cin>>s;
+        long long a=0;
+        for(long long i=0; i<n; i++) {
+            if(s[i]=='(') a++;
+            if(s[i]==')') a--;
+            if(s[i]=='_') {
+                if (a>0) {
+                    s[i]=')';
+                    a--;
+                }
+                else {
+                    s[i]='(';
+                    a++;
+                }
+            }
+        }
+        long long ans=0;
+        vector <long long> o, c;
+        for(long long i=0; i<n; i++) {
+            if(s[i]=='(') o.push_back(i);
+            else c.push_back(i);
+        }
+        for(long long i=0; i<n/2; i++) ans+=(c[i]-o[i]);
+        cout<<ans<<endl;
+    }
+}