八十分代码！！！

哪位大佬帮忙修一下呀！！！

#include<bits/stdc++.h>
using namespace std;
#define int long long
#define double long double

struct birth{
   string s;
   int y,m,d;
}k[1005];
bool cmp(birth a,birth b){
   if(a.y==b.y){
       if(a.m==b.m) return a.d<b.d;
       else return a.m<b.m;
   }
   else return a.y<b.y;
}
int n;
signed main(){
   cin>>n;
   for(int i=0;i<n;i++) cin>>k[i].s>>k[i].y>>k[i].m>>k[i].d;
   sort(k,k+n,cmp);
   for(int i=0;i<n;i++) cout<<k[i].s<<"\n";
   
   return 0;
}