巨简单！

#include<bits/stdc++.h>
using namespace std;
int a[10000001];
int main(){
int n,i,k,s=1;
cin>>n;
for (i=0;i<n;i++) cin>>a[i];
sort(a,a+n);
a[n]=-10000000;
for (i=1;i<=n;i++)
if (a[i]==a[i-1]) s++;
else {cout<<a[i-1]<<' '<<s<<endl;s=1;}
return 0;
}