1:
#include<iostream>
#include<cmath>
using namespace std;
int main() {
int n,a,m=0;
cin >> n;
int ar[n];
for (int i = 0; i < n; i++) {
cin >> ar[i];
}
cin>>a;
for(int j=0;j<n;j++){
if(ar[j]==a){
m++;
}
}
cout<<m;
}
2:
#include<iostream>
#include<cmath>
using namespace std;
int main() {
int n,a,m=0;
cin >> n;
int ar[n],br[n];
for (int i = 0; i < n; i++) {
cin >> ar[i];
}
cin>>a;
for(int j=0;j<n;j++){
if(ar[j]==a){
m++;
br[j]=j;
}
}
cout<<m<<endl;
for(int k=0;k<n;k++){
if(br[k]==k){
cout<<k+1<<' ';
}
}
}