最坑的地方：保留一位小数

#include <iostream>
using namespace std;
struct student{
string name;
double mark;
int age;
}a[110];
int main (){
int n;
cin>>n;
for (int i=0;i<n;i++){
cin>>a[i].name>>a[i].mark>>a[i].age;
}
for (int i=0;i<n;i++){
cout<<a[i].name<<" ";
printf ("%.1f",a[i].mark);
cout<<" "<<a[i].age<<'\n';
}
return 0;
}