a code about stuct,l dont know much abou it, please help me to find out my mistakes

Question

input number n, and input n students' information(include his id, name, and 5 grades), get the sum of 5 grades.According to his total score , order the student from high to low.(my code is following)

Answer 1

//thank you!
#include <iostream>
using namespace std;

template<class T>
void myswap (T&x,T&y) { //change x to y,change y to x
T temp=x;
x=y;
y=temp;}

template<class T>
void bubbleSort (T a[ ],int n) {
int i=n-1;
while(i>0) {
int lastexchangeindex=0;
for(int j=0; j<i; j++)
{
if (a[ j+1]>a[ j])
{myswap(a[ j],a[ j+1]);
lastexchangeindex=j;}
}
i=lastexchangeindex;
}
}

struct student{
int num;
string name;
int grade1;
int grade2;
int grade3;
int grade4;
int grade5;
};
int main() {
int n;
cin>>n;
student object[n];
for(int x=0;x<n;x++) //imput
cin>>object[n]>>endl;
int score[n];
for(int x=0;x<n;x++) //get the totall score of 5 grades and order the student from large to small

{ score[n]=object[n].grade1+object[n].grade2+object[n].grade3+object[n].grade4+object[n].grade5;
if(score[n]<score[n+1])
bubbleSort(object[n],object[n+1]) }
for(int x=0;x<n;x++) //output
cout<<object[n]<<endl;
return 0;
}

Answer 2

l m learning c++ by myself...l dont konw how to corret this code