Language: C++

    //dhruv
    #include<bits/stdc++.h>
    using namespace std;
     
    #define int long long
    #define ffor(i,n) for(int i = 0;i < int(n); ++i)
    #define fro(i,j,n) for(int i = (j);i < (n); ++i)
    #define all(v) v.begin(),v.end()
    #define vi vector<int>
    #define vvi vector<vi>
    #define pii pair<int,int>
    #define vpii vector<pii>
    #define ff first
    #define ss second
     
     
    signed main(){
        ios_base::sync_with_stdio(0);
        cin.tie(0);
        mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
        string s;
        cin >> s;
        ffor(i,s.length()){
        	if(s[i] == '7'){
        		cout << "YES";
        		return 0;
        	}
        }
        cout << "NO";
    }		

Compiler output:
a.cc: In function 'int main()':
a.cc:5:17: error: expected primary-expression before 'long'
    5 |     #define int long long
      |                 ^~~~
a.cc:6:41: note: in expansion of macro 'int'
    6 |     #define ffor(i,n) for(int i = 0;i < int(n); ++i)
      |                                         ^~~
a.cc:23:9: note: in expansion of macro 'ffor'
   23 |         ffor(i,s.length()){
      |         ^~~~
a.cc:5:17: error: expected ';' before 'long'
    5 |     #define int long long
      |                 ^~~~
a.cc:6:41: note: in expansion of macro 'int'
    6 |     #define ffor(i,n) for(int i = 0;i < int(n); ++i)
      |                                         ^~~
a.cc:23:9: note: in expansion of macro 'ffor'
   23 |         ffor(i,s.length()){
      |         ^~~~
a.cc:5:17: error: expected primary-expression before 'long'
    5 |     #define int long long
      |                 ^~~~
a.cc:6:41: note: in expansion of macro 'int'
    6 |     #define ffor(i,n) for(int i = 0;i < int(n); ++i)
      |                                         ^~~
a.cc:23:9: note: in expansion of macro 'ffor'
   23 |         ffor(i,s.length()){
      |         ^~~~
a.cc:5:17: error: expected ')' before 'long'
    5 |     #define int long long
      |                 ^~~~
a.cc:6:41: note: in expansion of macro 'int'
    6 |     #define ffor(i,n) for(int i = 0;i < int(n); ++i)
      |                                         ^~~
a.cc:23:9: note: in expansion of macro 'ffor'
   23 |         ffor(i,s.length()){
      |         ^~~~
a.cc:6:26: note: to match this '('
    6 |     #define ffor(i,n) for(int i = 0;i < int(n); ++i)
      |                          ^
a.cc:23:9: note: in expansion of macro 'ffor'
   23 |         ffor(i,s.length()){
      |         ^~~~
a.cc:5:17: error: expected primary-expression before 'long'
    5 |     #define int long long
      |                 ^~~~
a.cc:6:41: note: in expansion of macro 'int'
    6 |     #define ffor(i,n) for(int i = 0;i < int(n); ++i)
      |                                         ^~~
a.cc:23:9: note: in expansion of macro 'ffor'
   23 |         ffor(i,s.length()){
      |         ^~~~
a.cc:23:14: error: 'i' was not declared in this scope
   23 |         ffor(i,s.length()){
      |              ^
a.cc:6:51: note: in definition of macro 'ffor'
    6 |     #define ffor(i,n) for(int i = 0;i < int(n); ++i)
      |                                                   ^