CodeGraderBench/CodeGraderBench huggingface dataset:
Problem: A sequence of characters ‘(‘ and ‘)’ is said to be balanced or valid, if it can be obtained from a valid mathematical expression by erasing all other symbols. For instance, from a mathematical expression like (1+2)*((3+4)*(1+2)) yields a balanced sequence ()(()()). On the other hand, the sequence (() or the sequence )( is not balanced. Write a C++ program to read a sequence of characters consisting of characters ‘(‘ and ‘)’ and identify if it is VALID or INVALID. To check whether a sequence is valid, it is enough to keep track of the count of ‘(‘s and ‘)’s seen at any point in the sequence, when scanning the sequence left to right. You can use a few examples to understand when a sequence becomes invalid. 
Input Format
A non-negative integer n, followed by a sequence of n characters consisting of ‘(’ and ‘)’  

Output Format
VALID N
or
INVALID N 

where N = openCount - closeCount, where openCount is the number of  ‘(’ symbols and  closeCount is the number of  ‘)’ symbols in the sequence.

Student submission:
#include <iostream>
using namespace std;
int main () {
        int n;
        cin>>n;
        int open, close;
        bool error=false;
        while(n--) {
                char a;
                cin>>a;
                if (close>open) {
                        error=true;
                        if (a=='(') ++open;
                        else ++close;
                }
                else if (a=='(') ++open;
                else ++close;
        }
        if (error) cout<<"INVALID "<<(open-close)<<endl;
        else if (open==close) cout<<"VALID "<<0<<endl;
        else cout<<"INVALID "<<(open-close)<<endl;
        return 0;
}

Grading criterion: Declaration of variables and accepting input
Rating A: correctly declared and accepts input for the variable n and char for accepting paranthesis
Rating B: Some issue
Rating C: Major issue
Rating D: 0
Assigned grade: A
Problem: A sequence of characters ‘(‘ and ‘)’ is said to be balanced or valid, if it can be obtained from a valid mathematical expression by erasing all other symbols. For instance, from a mathematical expression like (1+2)*((3+4)*(1+2)) yields a balanced sequence ()(()()). On the other hand, the sequence (() or the sequence )( is not balanced. Write a C++ program to read a sequence of characters consisting of characters ‘(‘ and ‘)’ and identify if it is VALID or INVALID. To check whether a sequence is valid, it is enough to keep track of the count of ‘(‘s and ‘)’s seen at any point in the sequence, when scanning the sequence left to right. You can use a few examples to understand when a sequence becomes invalid. 
Input Format
A non-negative integer n, followed by a sequence of n characters consisting of ‘(’ and ‘)’  

Output Format
VALID N
or
INVALID N 

where N = openCount - closeCount, where openCount is the number of  ‘(’ symbols and  closeCount is the number of  ‘)’ symbols in the sequence.

Student submission:
#include <simplecpp>
main_program {
        int n;
        cin >> n;
        int i=n-1;
        int openc=0,closec=0;
        char s;
        cin >> s;
        if ( s==')') {
                closec++;
                for (;i>0;i--){
                char b;
                cin >> b;
                if (b==')') closec++;
                else openc++;
                }
                float N = openc-closec;
                cout << "INVALID " << N;


        }
        else {
                openc++;
                for(;i>0;i--){
                char b;
                cin >> b;
                if (b==')') closec++;
                else openc++;
                }
                float N = openc-closec;
                if (N==0) cout << "VALID " << N;
                else cout << "INVALID " << N;
                }
}

Grading criterion: Declaration of variables and accepting input
Rating A: correctly declared and accepts input for the variable n and char for accepting paranthesis
Rating B: Some issue
Rating C: Major issue
Rating D: 0
Assigned grade: A
Problem: A sequence of characters ‘(‘ and ‘)’ is said to be balanced or valid, if it can be obtained from a valid mathematical expression by erasing all other symbols. For instance, from a mathematical expression like (1+2)*((3+4)*(1+2)) yields a balanced sequence ()(()()). On the other hand, the sequence (() or the sequence )( is not balanced. Write a C++ program to read a sequence of characters consisting of characters ‘(‘ and ‘)’ and identify if it is VALID or INVALID. To check whether a sequence is valid, it is enough to keep track of the count of ‘(‘s and ‘)’s seen at any point in the sequence, when scanning the sequence left to right. You can use a few examples to understand when a sequence becomes invalid. 
Input Format
A non-negative integer n, followed by a sequence of n characters consisting of ‘(’ and ‘)’  

Output Format
VALID N
or
INVALID N 

where N = openCount - closeCount, where openCount is the number of  ‘(’ symbols and  closeCount is the number of  ‘)’ symbols in the sequence.

Student submission:
#include<simplecpp>
int main(){
    int n;cin>>n;
    bool val = true;
    int r=0,l=0;
    for (int i=0;i<n;i++){
        char a;cin>>a;
        if (i==0 && a==')'){val =false;}
        if (a=='(' && i==n-1) val= false;
        if (a=='(') r++;
        else l++;
        if ((r-l)<0) val = false ;
    }
    if (r!=l){val=false;}
    if (val) cout<<"VALID "<<r-l;
    else cout<<"INVALID "<<r-l;
}

Grading criterion: Declaration of variables and accepting input
Rating A: correctly declared and accepts input for the variable n and char for accepting paranthesis
Rating B: Some issue
Rating C: Major issue
Rating D: 0
Assigned grade: A
Problem: A sequence of characters ‘(‘ and ‘)’ is said to be balanced or valid, if it can be obtained from a valid mathematical expression by erasing all other symbols. For instance, from a mathematical expression like (1+2)*((3+4)*(1+2)) yields a balanced sequence ()(()()). On the other hand, the sequence (() or the sequence )( is not balanced. Write a C++ program to read a sequence of characters consisting of characters ‘(‘ and ‘)’ and identify if it is VALID or INVALID. To check whether a sequence is valid, it is enough to keep track of the count of ‘(‘s and ‘)’s seen at any point in the sequence, when scanning the sequence left to right. You can use a few examples to understand when a sequence becomes invalid. 
Input Format
A non-negative integer n, followed by a sequence of n characters consisting of ‘(’ and ‘)’  

Output Format
VALID N
or
INVALID N 

where N = openCount - closeCount, where openCount is the number of  ‘(’ symbols and  closeCount is the number of  ‘)’ symbols in the sequence.

Student submission:
#include <simplecpp>
main_program{
    int n,N,openCount=0,closeCount=0;
    char c;
    cin >> n;
    bool isValid = true;
    if(n==0){
        cout << "VALID 0";
    }
    
    else{
    for(int i=0;i<n;++i){
        cin>>c;
        if(c == '('){
            openCount += 1;
         }
        if(c == ')'){
            closeCount += 1;
            }
        if(openCount-closeCount < 0){
            isValid = false;
        }
    }
    N=openCount-closeCount;
    if (isValid==true && N == 0){
        cout<< "VALID " << N;
    }
    else {cout<< "INVALID " << N;}
    }
}

Grading criterion: Declaration of variables and accepting input
Rating A: correctly declared and accepts input for the variable n and char for accepting paranthesis
Rating B: Some issue
Rating C: Major issue
Rating D: 0
Assigned grade: A
Problem: A sequence of characters ‘(‘ and ‘)’ is said to be balanced or valid, if it can be obtained from a valid mathematical expression by erasing all other symbols. For instance, from a mathematical expression like (1+2)*((3+4)*(1+2)) yields a balanced sequence ()(()()). On the other hand, the sequence (() or the sequence )( is not balanced. Write a C++ program to read a sequence of characters consisting of characters ‘(‘ and ‘)’ and identify if it is VALID or INVALID. To check whether a sequence is valid, it is enough to keep track of the count of ‘(‘s and ‘)’s seen at any point in the sequence, when scanning the sequence left to right. You can use a few examples to understand when a sequence becomes invalid. 
Input Format
A non-negative integer n, followed by a sequence of n characters consisting of ‘(’ and ‘)’  

Output Format
VALID N
or
INVALID N 

where N = openCount - closeCount, where openCount is the number of  ‘(’ symbols and  closeCount is the number of  ‘)’ symbols in the sequence.

Student submission:
#include<simplecpp>
main_program{
	int c1=0,c2=0,n;
	cin>>n;
	bool flag=false;
	for(int it=0;it<n;it++){
		char c;
		cin>>c;
		if(c=='(') c1++;
		else if(c==')') c2++;
		if(c1<c2){
			c1++;
			flag=true;
		  	break;
		}
	}
	if((c1==c2)&&(!flag)) cout<<"VALID"<<" "<<(c1-c2);
	else cout<<"INVALID"<<" "<<(c1-c2);
}

Grading criterion: Declaration of variables and accepting input
Rating A: correctly declared and accepts input for the variable n and char for accepting paranthesis
Rating B: Some issue
Rating C: Major issue
Rating D: 0
Assigned grade: A
Problem: A sequence of characters ‘(‘ and ‘)’ is said to be balanced or valid, if it can be obtained from a valid mathematical expression by erasing all other symbols. For instance, from a mathematical expression like (1+2)*((3+4)*(1+2)) yields a balanced sequence ()(()()). On the other hand, the sequence (() or the sequence )( is not balanced. Write a C++ program to read a sequence of characters consisting of characters ‘(‘ and ‘)’ and identify if it is VALID or INVALID. To check whether a sequence is valid, it is enough to keep track of the count of ‘(‘s and ‘)’s seen at any point in the sequence, when scanning the sequence left to right. You can use a few examples to understand when a sequence becomes invalid. 
Input Format
A non-negative integer n, followed by a sequence of n characters consisting of ‘(’ and ‘)’  

Output Format
VALID N
or
INVALID N 

where N = openCount - closeCount, where openCount is the number of  ‘(’ symbols and  closeCount is the number of  ‘)’ symbols in the sequence.

Student submission:
#include<simplecpp>
void openCount(char b='('){
    for(int i=0;i==b;i++){
        b='(';
        i++;
        cout<<i<<endl;
    }
}
int main(){
    int n;
    char b='(';
    cin>>n>>b;
    openCount(b);
}

Grading criterion: Declaration of variables and accepting input
Rating A: correctly declared and accepts input for the variable n and char for accepting paranthesis
Rating B: Some issue
Rating C: Major issue
Rating D: 0
Assigned grade: A
Problem: A sequence of characters ‘(‘ and ‘)’ is said to be balanced or valid, if it can be obtained from a valid mathematical expression by erasing all other symbols. For instance, from a mathematical expression like (1+2)*((3+4)*(1+2)) yields a balanced sequence ()(()()). On the other hand, the sequence (() or the sequence )( is not balanced. Write a C++ program to read a sequence of characters consisting of characters ‘(‘ and ‘)’ and identify if it is VALID or INVALID. To check whether a sequence is valid, it is enough to keep track of the count of ‘(‘s and ‘)’s seen at any point in the sequence, when scanning the sequence left to right. You can use a few examples to understand when a sequence becomes invalid. 
Input Format
A non-negative integer n, followed by a sequence of n characters consisting of ‘(’ and ‘)’  

Output Format
VALID N
or
INVALID N 

where N = openCount - closeCount, where openCount is the number of  ‘(’ symbols and  closeCount is the number of  ‘)’ symbols in the sequence.

Student submission:
#include<simplecpp>
main_program{
	int n;
	cin>>n;
	int a=0,b=0,m=0;
	for(int i=1;i<=n;i++){
		char ch;
		cin>>ch;
		if(ch=='('){a++;}
		else if(ch==')'){b++;}
		if(b>a){m++;}
	}
	if(a!=b || m!=0){cout<<"Invalid "<<a-b;}
	else {cout<<"Valid "<<a-b;}
}

Grading criterion: Declaration of variables and accepting input
Rating A: correctly declared and accepts input for the variable n and char for accepting paranthesis
Rating B: Some issue
Rating C: Major issue
Rating D: 0
Assigned grade: A
Problem: A sequence of characters ‘(‘ and ‘)’ is said to be balanced or valid, if it can be obtained from a valid mathematical expression by erasing all other symbols. For instance, from a mathematical expression like (1+2)*((3+4)*(1+2)) yields a balanced sequence ()(()()). On the other hand, the sequence (() or the sequence )( is not balanced. Write a C++ program to read a sequence of characters consisting of characters ‘(‘ and ‘)’ and identify if it is VALID or INVALID. To check whether a sequence is valid, it is enough to keep track of the count of ‘(‘s and ‘)’s seen at any point in the sequence, when scanning the sequence left to right. You can use a few examples to understand when a sequence becomes invalid. 
Input Format
A non-negative integer n, followed by a sequence of n characters consisting of ‘(’ and ‘)’  

Output Format
VALID N
or
INVALID N 

where N = openCount - closeCount, where openCount is the number of  ‘(’ symbols and  closeCount is the number of  ‘)’ symbols in the sequence.

Student submission:
#include<simplecpp>
main_program{
    int n;
    int openCount = 0 , closeCount = 0 ;
    cin>>n;
    for (int i = 1 ; i< n ;++i){
        char a;
        cin>>a;
        if(a=='('){++openCount ;}
        else {++closeCount;}
    }
    char a ;
    cin>> a;
    if(a=='('){++openCount;}
    else {++closeCount;}
    int N = openCount-closeCount;
    if(N==0 && a==')'){
        cout<<"VALID"<<" "<<N ;
    }
    else {
        cout<<"INVALID"<<" "<<N;
    }
}

Grading criterion: Declaration of variables and accepting input
Rating A: correctly declared and accepts input for the variable n and char for accepting paranthesis
Rating B: Some issue
Rating C: Major issue
Rating D: 0
Assigned grade: A
Problem: A sequence of characters ‘(‘ and ‘)’ is said to be balanced or valid, if it can be obtained from a valid mathematical expression by erasing all other symbols. For instance, from a mathematical expression like (1+2)*((3+4)*(1+2)) yields a balanced sequence ()(()()). On the other hand, the sequence (() or the sequence )( is not balanced. Write a C++ program to read a sequence of characters consisting of characters ‘(‘ and ‘)’ and identify if it is VALID or INVALID. To check whether a sequence is valid, it is enough to keep track of the count of ‘(‘s and ‘)’s seen at any point in the sequence, when scanning the sequence left to right. You can use a few examples to understand when a sequence becomes invalid. 
Input Format
A non-negative integer n, followed by a sequence of n characters consisting of ‘(’ and ‘)’  

Output Format
VALID N
or
INVALID N 

where N = openCount - closeCount, where openCount is the number of  ‘(’ symbols and  closeCount is the number of  ‘)’ symbols in the sequence.

Student submission:
#include <simplecpp>
main_program{
	int a,c,d;
	cin>>a;
	c=0;
	for(int i=0;i<a;i++){
		char b;
		cin>>b;
		if(b=='('){
			c=c+1;
		}
		else c=c-1;
		if (i<a-1 && c==0){
			d=d+1;
		}
	}
	if(c==0 && d==0){
		cout<<"VALID 0";
	}
	else {
		cout<<"INVALID"<<" "<<c;
	}
}

Grading criterion: Declaration of variables and accepting input
Rating A: correctly declared and accepts input for the variable n and char for accepting paranthesis
Rating B: Some issue
Rating C: Major issue
Rating D: 0
Assigned grade: A
Problem: A sequence of characters ‘(‘ and ‘)’ is said to be balanced or valid, if it can be obtained from a valid mathematical expression by erasing all other symbols. For instance, from a mathematical expression like (1+2)*((3+4)*(1+2)) yields a balanced sequence ()(()()). On the other hand, the sequence (() or the sequence )( is not balanced. Write a C++ program to read a sequence of characters consisting of characters ‘(‘ and ‘)’ and identify if it is VALID or INVALID. To check whether a sequence is valid, it is enough to keep track of the count of ‘(‘s and ‘)’s seen at any point in the sequence, when scanning the sequence left to right. You can use a few examples to understand when a sequence becomes invalid. 
Input Format
A non-negative integer n, followed by a sequence of n characters consisting of ‘(’ and ‘)’  

Output Format
VALID N
or
INVALID N 

where N = openCount - closeCount, where openCount is the number of  ‘(’ symbols and  closeCount is the number of  ‘)’ symbols in the sequence.

Student submission:
#include<simplecpp>

main_program{
    int n; cin >> n;
    int s=0;
    bool valid = 1;
    for(int i=0; i<n; i++) {
        char par; cin >> par;
        if(par == '(') s++;
        else if(par == ')') s--;
        if(s < 0) valid = 0;
    }
    if(s!=0) valid = 0;
    cout << (valid ? "VALID" : "INVALID") << " " << s;
}

Grading criterion: Declaration of variables and accepting input
Rating A: correctly declared and accepts input for the variable n and char for accepting paranthesis
Rating B: Some issue
Rating C: Major issue
Rating D: 0
Assigned grade: A
Problem: A sequence of characters ‘(‘ and ‘)’ is said to be balanced or valid, if it can be obtained from a valid mathematical expression by erasing all other symbols. For instance, from a mathematical expression like (1+2)*((3+4)*(1+2)) yields a balanced sequence ()(()()). On the other hand, the sequence (() or the sequence )( is not balanced. Write a C++ program to read a sequence of characters consisting of characters ‘(‘ and ‘)’ and identify if it is VALID or INVALID. To check whether a sequence is valid, it is enough to keep track of the count of ‘(‘s and ‘)’s seen at any point in the sequence, when scanning the sequence left to right. You can use a few examples to understand when a sequence becomes invalid. 
Input Format
A non-negative integer n, followed by a sequence of n characters consisting of ‘(’ and ‘)’  

Output Format
VALID N
or
INVALID N 

where N = openCount - closeCount, where openCount is the number of  ‘(’ symbols and  closeCount is the number of  ‘)’ symbols in the sequence.

Student submission:
#include<iostream>
using namespace std;

int main(){
    int N, openCnt, balance, closeCnt;
    bool validity = true;
    cin >> N;
    openCnt = 0;
    closeCnt = 0;
    int unmatchedOpen = 0;
    for(int i = 0; i < N; i++){
        char C;
        cin >> C;
        if(C == '('){
            openCnt++;
            unmatchedOpen++;
        }
        else if(C == ')'){
            closeCnt++;
            if(unmatchedOpen != 0){
                unmatchedOpen--;
            }
        }
        balance = openCnt-closeCnt;
    }
    if(balance != 0){
        cout << "INVALID " << balance;
    }
    else{
        if(unmatchedOpen != 0){
            cout << "INVALID " << balance;
        }
        else{
            cout << "VALID " << balance;
        }
    }



}

Grading criterion: Loop to iterate from 1 to n
Rating A: correctly iterates the loop to accept all the n characters
Rating B: Some issue
Rating C: Major issue
Rating D: 0
Assigned grade: A
Problem: A sequence of characters ‘(‘ and ‘)’ is said to be balanced or valid, if it can be obtained from a valid mathematical expression by erasing all other symbols. For instance, from a mathematical expression like (1+2)*((3+4)*(1+2)) yields a balanced sequence ()(()()). On the other hand, the sequence (() or the sequence )( is not balanced. Write a C++ program to read a sequence of characters consisting of characters ‘(‘ and ‘)’ and identify if it is VALID or INVALID. To check whether a sequence is valid, it is enough to keep track of the count of ‘(‘s and ‘)’s seen at any point in the sequence, when scanning the sequence left to right. You can use a few examples to understand when a sequence becomes invalid. 
Input Format
A non-negative integer n, followed by a sequence of n characters consisting of ‘(’ and ‘)’  

Output Format
VALID N
or
INVALID N 

where N = openCount - closeCount, where openCount is the number of  ‘(’ symbols and  closeCount is the number of  ‘)’ symbols in the sequence.

Student submission:
#include<simplecpp>
main_program{
	int n,c=0;
	char s;
	cin>>n;
	bool e=true;
	for(int i=0;i<n;i++){
		cin>>s;
		if(s == '(')
			c++;
		if(s == ')')
			c--;
		if(c<0) e=false;
	}
	if(c !=0) e=false;
	if(e) cout<<"VALID ";
	else cout<<"INVALID ";
	cout<<c;
}

Grading criterion: Loop to iterate from 1 to n
Rating A: correctly iterates the loop to accept all the n characters
Rating B: Some issue
Rating C: Major issue
Rating D: 0
Assigned grade: A
Problem: A sequence of characters ‘(‘ and ‘)’ is said to be balanced or valid, if it can be obtained from a valid mathematical expression by erasing all other symbols. For instance, from a mathematical expression like (1+2)*((3+4)*(1+2)) yields a balanced sequence ()(()()). On the other hand, the sequence (() or the sequence )( is not balanced. Write a C++ program to read a sequence of characters consisting of characters ‘(‘ and ‘)’ and identify if it is VALID or INVALID. To check whether a sequence is valid, it is enough to keep track of the count of ‘(‘s and ‘)’s seen at any point in the sequence, when scanning the sequence left to right. You can use a few examples to understand when a sequence becomes invalid. 
Input Format
A non-negative integer n, followed by a sequence of n characters consisting of ‘(’ and ‘)’  

Output Format
VALID N
or
INVALID N 

where N = openCount - closeCount, where openCount is the number of  ‘(’ symbols and  closeCount is the number of  ‘)’ symbols in the sequence.

Student submission:
#include<simplecpp>
main_program{
	int n;
	int count1=0,count2=0,order=0;
	cin>>n;
	char ch;
	repeat(n)
	{
		cin>>ch;
		if(ch=='(')
			count1++;
		if(ch==')')
			count2++;
		if(count2>count1)
		{
			order++;
		}
	}
	if(order!=0)
		cout<<"INVALID "<<count1-count2;
	else if(count1==count2)
	{
		cout<<"VALID 0";}
	else
		cout<<"INVALID "<<count1-count2;
	return 0;
}

Grading criterion: Loop to iterate from 1 to n
Rating A: correctly iterates the loop to accept all the n characters
Rating B: Some issue
Rating C: Major issue
Rating D: 0
Assigned grade: A
Problem: A sequence of characters ‘(‘ and ‘)’ is said to be balanced or valid, if it can be obtained from a valid mathematical expression by erasing all other symbols. For instance, from a mathematical expression like (1+2)*((3+4)*(1+2)) yields a balanced sequence ()(()()). On the other hand, the sequence (() or the sequence )( is not balanced. Write a C++ program to read a sequence of characters consisting of characters ‘(‘ and ‘)’ and identify if it is VALID or INVALID. To check whether a sequence is valid, it is enough to keep track of the count of ‘(‘s and ‘)’s seen at any point in the sequence, when scanning the sequence left to right. You can use a few examples to understand when a sequence becomes invalid. 
Input Format
A non-negative integer n, followed by a sequence of n characters consisting of ‘(’ and ‘)’  

Output Format
VALID N
or
INVALID N 

where N = openCount - closeCount, where openCount is the number of  ‘(’ symbols and  closeCount is the number of  ‘)’ symbols in the sequence.

Student submission:
#include<simplecpp>
main_program
{   
    bool validity= true;
    int n;
    char c;
    int N=0;
    cin>>n;
    repeat(n)
    {
        cin>>c;
        if(c=='(')
        N++;
        else if(c==')'&&N<=0)
        {
            validity = false;
            N--;
        }
        else if(c==')')
        N--;
    }
    if(validity)
    {
        if(N==0)
        cout<<"VALID "<<N;
        else
        cout<<"INVALID "<<N;
    

    }
    else cout<<"INVALID "<<N;
}

Grading criterion: Loop to iterate from 1 to n
Rating A: correctly iterates the loop to accept all the n characters
Rating B: Some issue
Rating C: Major issue
Rating D: 0
Assigned grade: A