C++ Code to Find Rank of Student from Score Table

Suppose we have a 2d array of size n x 4. Consider there are n students and their ids are starting from 0 to n-1. Each of them has four scores on English, Geography, Maths and History. In the table, the students will be sorted by decreasing the sum of their scores. If two or more students have the same sum, these students will be sorted by increasing their ids. We have to find the id of student whose id is 0.

So, if the input is like

then the output will be 2

Steps

To solve this, we will follow these steps −

n := size of table
r := 1
p := table[0, 0] + table[0, 1] + table[0, 2] + table[0, 3]
for initialize i := 1, when i < n, update (increase i by 1), do:
   if table[i, 0] + table[i, 1] + table[i, 2] + table[i, 3] > p,
then:
   (increase r by 1)
return r

Example

Let us see the following implementation to get better understanding −

#include <bits/stdc++.h>
using namespace std;
int solve(vector<vector<int>> table){
   int n = table.size();
   int r = 1;
   int p = table[0][0] + table[0][1] + table[0][2] + table[0][3];
   for (int i = 1; i < n; i++){
      if (table[i][0] + table[i][1] + table[i][2] + table[i][3] > p)
         r++;
   }
   return r;
}
int main(){
   vector<vector<int>> table = { { 100, 98, 100, 100 }, { 100, 100, 100, 100 }, { 90, 99, 90, 100 }, { 100, 98, 60, 99 } };
   cout << solve(table) << endl;
}

Input

{ { 100, 98, 100, 100 }, { 100, 100, 100, 100 }, { 90, 99, 90, 100 }, { 100, 98, 60, 99 } }

Output

2