Language: C++

#include<iostream>
#include<stdio.h>
#define N 30
using namespace std;
int main(){
????int w,n,tmp;
????int lod[N]; int lis[N][3];
????while(cin >> n >> w){
????for(int i = 0;i<n;i++){
????lod[i] = i+1;
????}
????for(int i=0;i<w;i++){
????scanf("%d,%d",&lis[i][0],&lis[i][2]);
????}
????for(int i=0;i<w;i++){
????tmp = lod[lis[i][0]-1];
????lod[lis[i][0]-1] = lod[lis[i][2]-1];
????lod[lis[i][2]-1] = tmp;
????}
????for(int i=0;i<n;i++){
????cout << lod[i] << endl;
????}
  return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:6:1: error: expected primary-expression before '?' token
    6 | ????int w,n,tmp;
      | ^
a.cc:6:2: error: expected primary-expression before '?' token
    6 | ????int w,n,tmp;
      |  ^
a.cc:6:3: error: expected primary-expression before '?' token
    6 | ????int w,n,tmp;
      |   ^
a.cc:6:4: error: expected primary-expression before '?' token
    6 | ????int w,n,tmp;
      |    ^
a.cc:6:5: error: expected primary-expression before 'int'
    6 | ????int w,n,tmp;
      |     ^~~
a.cc:6:5: error: expected ':' before 'int'
    6 | ????int w,n,tmp;
      |     ^~~
      |     :
a.cc:6:5: error: expected primary-expression before 'int'
    6 | ????int w,n,tmp;
      |     ^~~
a.cc:6:5: error: expected ':' before 'int'
    6 | ????int w,n,tmp;
      |     ^~~
      |     :
a.cc:6:5: error: expected primary-expression before 'int'
    6 | ????int w,n,tmp;
      |     ^~~
a.cc:6:5: error: expected ':' before 'int'
    6 | ????int w,n,tmp;
      |     ^~~
      |     :
a.cc:6:5: error: expected primary-expression before 'int'
    6 | ????int w,n,tmp;
      |     ^~~
a.cc:6:5: error: expected ':' before 'int'
    6 | ????int w,n,tmp;
      |     ^~~
      |     :
a.cc:6:5: error: expected primary-expression before 'int'
    6 | ????int w,n,tmp;
      |     ^~~
a.cc:7:1: error: expected primary-expression before '?' token
    7 | ????int lod[N]; int lis[N][3];
      | ^
a.cc:7:2: error: expected primary-expression before '?' token
    7 | ????int lod[N]; int lis[N][3];
      |  ^
a.cc:7:3: error: expected primary-expression before '?' token
    7 | ????int lod[N]; int lis[N][3];
      |   ^
a.cc:7:4: error: expected primary-expression before '?' token
    7 | ????int lod[N]; int lis[N][3];
      |    ^
a.cc:7:5: error: expected primary-expression before 'int'
    7 | ????int lod[N]; int lis[N][3];
      |     ^~~
a.cc:7:5: error: expected ':' before 'int'
    7 | ????int lod[N]; int lis[N][3];
      |     ^~~
      |     :
a.cc:7:5: error: expected primary-expression before 'int'
    7 | ????int lod[N]; int lis[N][3];
      |     ^~~
a.cc:7:5: error: expected ':' before 'int'
    7 | ????int lod[N]; int lis[N][3];
      |     ^~~
      |     :
a.cc:7:5: error: expected primary-expression before 'int'
    7 | ????int lod[N]; int lis[N][3];
      |     ^~~
a.cc:7:5: error: expected ':' before 'int'
    7 | ????int lod[N]; int lis[N][3];
      |     ^~~
      |     :
a.cc:7:5: error: expected primary-expression before 'int'
    7 | ????int lod[N]; int lis[N][3];
      |     ^~~
a.cc:7:5: error: expected ':' before 'int'
    7 | ????int lod[N]; int lis[N][3];
      |     ^~~
      |     :
a.cc:7:5: error: expected primary-expression before 'int'
    7 | ????int lod[N]; int lis[N][3];
      |     ^~~
a.cc:8:1: error: expected primary-expression before '?' token
    8 | ????while(cin >> n >> w){
      | ^
a.cc:8:2: error: expected primary-expression before '?' token
    8 | ????while(cin >> n >> w){
      |  ^
a.cc:8:3: error: expected primary-expression before '?' token
    8 | ????while(cin >> n >> w){
      |   ^
a.cc:8:4: error: expected primary-expression before '?' token
    8 | ????while(cin >> n >> w){
      |    ^
a.cc:8:5: error: expected primary-expression before 'while'
    8 | ????while(cin >> n >> w){
      |     ^~~~~
a.cc:8:5: error: expected ':' before 'while'
    8 | ????while(cin >> n >> w){
      |     ^~~~~
      |     :
a.cc:8:5: error: expected primary-expression before 'while'
    8 | ????while(cin >> n >> w){
      |     ^~~~~
a.cc:8:5: error: expected ':' before 'while'
    8 | ????while(cin >> n >> w){
      |     ^~~~~
      |     :
a.cc:8:5: error: expected primary-expression before 'while'
    8 | ????while(cin >> n >> w){
      |     ^~~~~
a.cc:8:5: error: expected ':' before 'while'
    8 | ????while(cin >> n >> w){
      |     ^~~~~
      |     :
a.cc:8:5: error: expected primary-expression before 'while'
    8 | ????while(cin >> n >> w){
      |     ^~~~~
a.cc:8:5: error: expected ':' before 'while'
    8 | ????while(cin >> n >> w){
      |     ^~~~~
      |     :
a.cc:8:5: error: expected primary-expression before 'while'
    8 | ????while(cin >> n >> w){
      |     ^~~~~
a.cc:24:2: error: expected '}' at end of input
   24 | }
      |  ^
a.cc:5:11: note: to match this '{'
    5 | int main(){
      |           ^