Different possible marks for n questions and negative marking - GeeksforGeeks

09 Mar, 2022
Given the number of questions as , and marks for the correct answer as and marks for the incorrect answer. One can either attempt to solve the question in an examination and get either marks if the answer is right, or marks if the answer is wrong, or leave the question unattended and get marks. The task is to find the count of all the different possible marks that one can score in the examination.Examples:  
Input: n = 2, p = 1, q = -1
Output: 5
The different possible marks are: -2, -1, 0, 1, 2

Input: n = 4, p = 2, q = -1
Output: 12
 
Approach: Iterate through all the possible number of correctly solved and unsolved problems. Store the scores in a set containing distinct elements keeping in mind that there is a positive number of incorrectly solved problems.Below is the implementation of the above approach:  
C++
Java
Python3
C#
Javascript
// CPP program to find the count of// all the different possible marks// that one can score in the examination#include<bits/stdc++.h> using namespace std;     // Function to return    // the count of distinct scores    int scores(int n, int p, int q)    {        // Set to store distinct values        set<int> hset;         // iterate through all        // possible pairs of (p, q)        for (int i = 0; i <= n; i++)        {            for (int j = 0; j <= n; j++)            {                 int correct = i;                int not_solved = j;                int incorrect = n - i - j;                 // if there are positive number                // of incorrectly solved problems                if (incorrect >= 0)                    hset.insert(p * correct                            + q * incorrect);                else                    break;            }        }         // return the size of the set        // containing distinct elements        return hset.size();    }     // Driver code    int main()    {         // Get the number of questions        int n = 4;         // Get the marks for correct answer        int p = 2;         // Get the marks for incorrect answer        int q = -1;         // Get the count and print it        cout << (scores(n, p, q));    } // This code is contributed by// Surendra_Gangwar
// Java program to find the count of// all the different possible marks// that one can score in the examination import java.util.*; class GFG {     // Function to return    // the count of distinct scores    static int scores(int n, int p, int q)    {        // Set to store distinct values        HashSet<Integer>            hset = new HashSet<Integer>();         // iterate through all        // possible pairs of (p, q)        for (int i = 0; i <= n; i++) {            for (int j = 0; j <= n; j++) {                 int correct = i;                int not_solved = j;                int incorrect = n - i - j;                 // if there are positive number                // of incorrectly solved problems                if (incorrect >= 0)                    hset.add(p * correct                             + q * incorrect);                else                    break;            }        }         // return the size of the set        // containing distinct elements        return hset.size();    }     // Driver code    public static void main(String[] args)    {         // Get the number of questions        int n = 4;         // Get the marks for correct answer        int p = 2;         // Get the marks for incorrect answer        int q = -1;         // Get the count and print it        System.out.println(scores(n, p, q));    }}
# Python3 program to find the count of# all the different possible marks# that one can score in the examination # Function to return the count of# distinct scoresdef scores(n, p, q):         # Set to store distinct values    hset = set()     # Iterate through all possible    # pairs of (p, q)    for i in range(0, n + 1):        for j in range(0, n + 1):             correct = i            not_solved = j            incorrect = n - i - j             # If there are positive number            # of incorrectly solved problems            if incorrect >= 0:                hset.add(p * correct +                         q * incorrect)            else:                break     # return the size of the set    # containing distinct elements    return len(hset)     # Driver codeif __name__ == "__main__":         # Get the number of questions    n = 4     # Get the marks for correct answer    p = 2     # Get the marks for incorrect answer    q = -1     # Get the count and print it    print(scores(n, p, q))     # This code is contributed by Rituraj Jain
// C# program to find the count of// all the different possible marks// that one can score in the examinationusing System;using System.Collections.Generic; class GFG{     // Function to return    // the count of distinct scores    static int scores(int n, int p, int q)    {        // Set to store distinct values        HashSet<int>            hset = new HashSet<int>();         // iterate through all        // possible pairs of (p, q)        for (int i = 0; i <= n; i++)        {            for (int j = 0; j <= n; j++)            {                 int correct = i;                int not_solved = j;                int incorrect = n - i - j;                 // if there are positive number                // of incorrectly solved problems                if (incorrect >= 0)                    hset.Add(p * correct                            + q * incorrect);                else                    break;            }        }         // return the size of the set        // containing distinct elements        return hset.Count;    }     // Driver code    public static void Main()    {         // Get the number of questions        int n = 4;         // Get the marks for correct answer        int p = 2;         // Get the marks for incorrect answer        int q = -1;         // Get the count and print it        Console.WriteLine(scores(n, p, q));    }} /* This code contributed by PrinciRaj1992 */
<script> // JavaScript program to find the count of// all the different possible marks// that one can score in the examination     // Function to return    // the count of distinct scores    function scores(n, p, q)    {        // Set to store distinct values        let hset = new Set();         // iterate through all        // possible pairs of (p, q)        for (let i = 0; i <= n; i++) {            for (let j = 0; j <= n; j++) {                 let correct = i;                let not_solved = j;                let incorrect = n - i - j;                 // if there are positive number                // of incorrectly solved problems                if (incorrect >= 0)                    hset.add(p * correct                             + q * incorrect);                else                    break;            }        }         // return the size of the set        // containing distinct elements        return hset.size;    }     // Driver Code            // Get the number of questions        let n = 4;         // Get the marks for correct answer        let p = 2;         // Get the marks for incorrect answer        let q = -1;         // Get the count and print it        document.write(scores(n, p, q));         </script>
12
 
rituraj_jain
SURENDRA_GANGWAR
princiraj1992
code_hunt
simranarora5sos
java-hashset
Combinatorial
Hash
Hash
Combinatorial
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