Language: C++

#include <bits/stdc++.h>
#include <set>
#define rep(i,n) for (int i=0; i < (n); ++i)
#define all(a) a.begin(), a.end()
using ll = long long;
using namespace std;
 

// 関数を作る
int gcd(int a, int b) {
  if (a == 0)
    return b;
  return gcd(b % a, a);
}
 
int main() {
  int a;
  cin >> a;
  int sum = 0;
  for (int i = 1; i <= a; i++) {
    for (int j = 1; j <= a; j++) {
      for (int k = 1; k <= a; k++) {
        sum += gcd(i, gcd(j, k));
      }
    }
  }
  cout << sum;
  return 0;
}

Compiler output:
a.cc:1:2: error: extended character   is not valid in an identifier
    1 | #include <bits/stdc++.h>
      |  ^
a.cc:1:2: error: invalid preprocessing directive #include\U000000a0
    1 | #include <bits/stdc++.h>
      |  ^~~~~~~~
a.cc:2:2: error: extended character   is not valid in an identifier
    2 | #include <set>
      |  ^
a.cc:2:2: error: invalid preprocessing directive #include\U000000a0
    2 | #include <set>
      |  ^~~~~~~~
a.cc:3:2: error: extended character   is not valid in an identifier
    3 | #define rep(i,n) for (int i=0; i < (n); ++i)
      |  ^
a.cc:3:2: error: invalid preprocessing directive #define\U000000a0rep
    3 | #define rep(i,n) for (int i=0; i < (n); ++i)
      |  ^~~~~~~~~~
a.cc:3:17: error: extended character   is not valid in an identifier
    3 | #define rep(i,n) for (int i=0; i < (n); ++i)
      |                 ^
a.cc:3:17: error: extended character   is not valid in an identifier
a.cc:3:23: error: extended character   is not valid in an identifier
    3 | #define rep(i,n) for (int i=0; i < (n); ++i)
      |                       ^
a.cc:3:31: error: extended character   is not valid in an identifier
    3 | #define rep(i,n) for (int i=0; i < (n); ++i)
      |                               ^
a.cc:3:31: error: extended character   is not valid in an identifier
a.cc:3:35: error: extended character   is not valid in an identifier
    3 | #define rep(i,n) for (int i=0; i < (n); ++i)
      |                                   ^
a.cc:3:40: error: extended character   is not valid in an identifier
    3 | #define rep(i,n) for (int i=0; i < (n); ++i)
      |                                        ^
a.cc:4:2: error: extended character   is not valid in an identifier
    4 | #define all(a) a.begin(), a.end()
      |  ^
a.cc:4:2: error: invalid preprocessing directive #define\U000000a0all
    4 | #define all(a) a.begin(), a.end()
      |  ^~~~~~~~~~
a.cc:4:15: error: extended character   is not valid in an identifier
    4 | #define all(a) a.begin(), a.end()
      |               ^
a.cc:4:26: error: extended character   is not valid in an identifier
    4 | #define all(a) a.begin(), a.end()
      |                          ^
a.cc:5:1: error: extended character   is not valid in an identifier
    5 | using ll = long long;
      | ^
a.cc:5:1: error: extended character   is not valid in an identifier
a.cc:5:11: error: extended character   is not valid in an identifier
    5 | using ll = long long;
      |           ^
a.cc:5:11: error: extended character   is not valid in an identifier
a.cc:6:1: error: extended character   is not valid in an identifier
    6 | using namespace std;
      | ^
a.cc:6:1: error: extended character   is not valid in an identifier
a.cc:7:1: error: extended character   is not valid in an identifier
    7 |  
      | ^
a.cc:10:1: error: extended character   is not valid in an identifier
   10 | int gcd(int a, int b) {
      | ^
a.cc:10:9: error: extended character   is not valid in an identifier
   10 | int gcd(int a, int b) {
      |         ^
a.cc:10:15: error: extended character   is not valid in an identifier
   10 | int gcd(int a, int b) {
      |               ^
a.cc:10:15: error: extended character   is not valid in an identifier
a.cc:10:22: error: extended character   is not valid in an identifier
   10 | int gcd(int a, int b) {
      |                      ^
a.cc:11:1: error: extended character   is not valid in an identifier
   11 |   if (a == 0)
      | ^
a.cc:11:1: error: extended character   is not valid in an identifier
a.cc:11:1: error: extended character   is not valid in an identifier
a.cc:11:7: error: extended character   is not valid in an identifier
   11 |   if (a == 0)
      |       ^
a.cc:11:11: error: extended character   is not valid in an identifier
   11 |   if (a == 0)
      |           ^
a.cc:12:1: error: extended character   is not valid in an identifier
   12 |     return b;
      | ^
a.cc:12:1: error: extended character   is not valid in an identifier
a.cc:12:1: error: extended character   is not valid in an identifier
a.cc:12:1: error: extended character   is not valid in an identifier
a.cc:12:1: error: extended character   is not valid in an identifier
a.cc:13:1: error: extended character   is not valid in an identifier
   13 |   return gcd(b % a, a);
      | ^
a.cc:13:1: error: extended character   is not valid in an identifier
a.cc:13:1: error: extended character   is not valid in an identifier
a.cc:13:14: error: extended character   is not valid in an identifier
   13 |   return gcd(b % a, a);
      |              ^
a.cc:13:17: error: extended character   is not valid in an identifier
   13 |   return gcd(b % a, a);
      |                 ^
a.cc:13:20: error: extended character   is not valid in an identifier
   13 |   return gcd(b % a, a);
      |                    ^
a.cc:15:1: error: extended character   is not valid in an identifier
   15 |  
      | ^
a.cc:16:1: error: extended character   is not valid in an identifier
   16 | int main() {
      | ^
a.cc:16:11: error: extended character   is not valid in an identifier
   16 | int main() {
      |           ^
a.cc:17:1: error: extended character   is not valid in an identifier
   17 |   int a;
      | ^
a.cc:17:1: error: extended character   is not valid in an identifier
a.cc:17:1: error: extended character   is not valid in an identifier
a.cc:18:1: error: extended character   is not valid in an identifier
   18 |   cin >> a;
      | ^
a.cc:18:1: error: extended character   is not valid in an identifier
a.cc:18:1: error: extended character   is not valid in an identifier
a.cc:18:9: error: extended character   is not valid in an identifier
   18 |   cin >> a;
      |         ^
a.cc:19:1: error: extended character   is not valid in an identifier
   19 |   int sum = 0;
      | ^
a.cc:19:1: error: extended character   is not valid in an identifier
a.cc:19:1: error: extended character   is not valid in an identifier
a.cc:19:1: error: extended character   is not valid in an identifier
a.cc:19:12: error: extended character   is not valid in an identifier
   19 |   int sum = 0;
      |            ^
a.cc:20:1: error: extended character   is not valid in an identifier
   20 |   for (int i = 1; i <= a; i++) {
      | ^
a.cc:20:1: error: extended character   is not valid in an identifier
a.cc:20:1: error: extended character   is not valid in an identifier
a.cc:20:8: error: extended character   is not valid in an identifier
   20 |   for (int i = 1; i <= a; i++) {
      |        ^
a.cc:20:8: error: extended character   is not valid in an identifier
a.cc:20:15: error: extended character   is not valid in an identifier
   20 |   for (int i = 1; i <= a; i++) {
      |               ^
a.cc:20:18: error: extended character   is not valid in an identifier
   20 |   for (int i = 1; i <= a; i++) {
      |                  ^
a.cc:20:18: error: extended character   is not valid in an identifier
a.cc:20:23: error: extended character   is not valid in an identifier
   20 |   for (int i = 1; i <= a; i++) {
      |                       ^
a.cc:20:26: error: extended character   is not valid in an identifier
   20 |   for (int i = 1; i <= a; i++) {
      |                          ^
a.cc:20:31: error: extended character   is not valid in an identifier
   20 |   for (int i = 1; i <= a; i++) {
      |                               ^
a.cc:21:1: error: extended character   is not valid in an identifier
   21 |     for (int j = 1; j <= a; j++) {
      | ^
a.cc:21:1: error: extended character   is not valid in an identifier
a.cc:21:1: error: extended character   is not valid in an identifier
a.cc:21:1: error: extended character   is not valid in an identifier
a.cc:21:1: error: extended character   is not valid in an identifier
a.cc:21:10: error: extended character   is not valid in an identifier
   21 |     for (int j = 1; j <= a; j++) {
      |          ^
a.cc:21:10: error: extended character   is not valid in an identifier
a.cc:21:17: error: extended character   is not valid in an identifier
   21 |     for (int j = 1; j <= a; j++) {
      |                 ^
a.cc:21:20: error: extended character   is not valid in an identifier
   21 |     for (int j = 1; j <= a; j++) {
      |                    ^
a.cc:21:20: error: extended character   is not valid in an identifier
a.cc:21:25: error: extended character   is not valid in an identifier
   21 |     for (int j = 1; j <= a; j++) {
      |                         ^
a.cc:21:28: error: extended character   is not valid in an identifier
   21 |     for (int j = 1; j <= a; j++) {
      |                            ^
a.cc:21:33: error: extended character   is not valid in an identifier
   21 |     for (int j = 1; j <= a; j++) {
      |                                 ^
a.cc:22:1: error: extended character   is not valid in an identifier
   22 |       for (int k = 1; k <= a; k++) {
      | ^
a.cc:22:1: error: extended character   is not valid in an identifier
a.cc:22:1: error: extended character   is not valid in an identifier
a.cc:22:1: error: extended character   is not valid in an identifier
a.cc:22:1: error: extended character   is not valid in an identifier
a.cc:22:1: error: extended character   is not valid in an identifier
a.cc:22:1: error: extended character   is not valid in an identifier
a.cc:22:12: error: extended character   is not valid in an identifier
   22 |       for (int k = 1; k <= a; k++) {
      |            ^
a.cc:22:12: error: extended character   is not valid in an identifier
a.cc:22:19: error: extended character   is not valid in an identifier
   22 |       for (int k = 1; k <= a; k++) {
      |                   ^
a.cc:22:22: error: extended character   is not valid in an identifier
   22 |       fo