Language: C++

#include<stdio.h>
int main(){
for(int ???=1;???<=9;???++)
for(int ???=1;???<=9;???++)printf("%dx%d=%d\n",???,???,???*???);
}

Compiler output:
a.cc:3:10: warning: trigraph ??= ignored, use -trigraphs to enable [-Wtrigraphs]
    3 | for(int ???=1;???<=9;???++)
a.cc:3:16: warning: trigraph ??< ignored, use -trigraphs to enable [-Wtrigraphs]
a.cc:4:10: warning: trigraph ??= ignored, use -trigraphs to enable [-Wtrigraphs]
    4 | for(int ???=1;???<=9;???++)printf("%dx%d=%d\n",???,???,???*???);
a.cc:4:16: warning: trigraph ??< ignored, use -trigraphs to enable [-Wtrigraphs]
a.cc:4:61: warning: trigraph ??) ignored, use -trigraphs to enable [-Wtrigraphs]
a.cc: In function 'int main()':
a.cc:3:9: error: expected unqualified-id before '?' token
    3 | for(int ???=1;???<=9;???++)
      |         ^
a.cc:3:8: error: expected ';' before '?' token
    3 | for(int ???=1;???<=9;???++)
      |        ^~
      |        ;
a.cc:3:9: error: expected primary-expression before '?' token
    3 | for(int ???=1;???<=9;???++)
      |         ^
a.cc:3:10: error: expected primary-expression before '?' token
    3 | for(int ???=1;???<=9;???++)
      |          ^
a.cc:3:11: error: expected primary-expression before '?' token
    3 | for(int ???=1;???<=9;???++)
      |           ^
a.cc:3:12: error: expected primary-expression before '=' token
    3 | for(int ???=1;???<=9;???++)
      |            ^
a.cc:3:14: error: expected ':' before ';' token
    3 | for(int ???=1;???<=9;???++)
      |              ^
      |              :
a.cc:3:14: error: expected primary-expression before ';' token
a.cc:3:14: error: expected ':' before ';' token
    3 | for(int ???=1;???<=9;???++)
      |              ^
      |              :
a.cc:3:14: error: expected primary-expression before ';' token
a.cc:3:14: error: expected ':' before ';' token
    3 | for(int ???=1;???<=9;???++)
      |              ^
      |              :
a.cc:3:14: error: expected primary-expression before ';' token
a.cc:3:15: error: expected primary-expression before '?' token
    3 | for(int ???=1;???<=9;???++)
      |               ^
a.cc:3:16: error: expected primary-expression before '?' token
    3 | for(int ???=1;???<=9;???++)
      |                ^
a.cc:3:17: error: expected primary-expression before '?' token
    3 | for(int ???=1;???<=9;???++)
      |                 ^
a.cc:3:18: error: expected primary-expression before '<=' token
    3 | for(int ???=1;???<=9;???++)
      |                  ^~
a.cc:3:21: error: expected ':' before ';' token
    3 | for(int ???=1;???<=9;???++)
      |                     ^
      |                     :
a.cc:3:21: error: expected primary-expression before ';' token
a.cc:3:21: error: expected ':' before ';' token
    3 | for(int ???=1;???<=9;???++)
      |                     ^
      |                     :
a.cc:3:21: error: expected primary-expression before ';' token
a.cc:3:21: error: expected ':' before ';' token
    3 | for(int ???=1;???<=9;???++)
      |                     ^
      |                     :
a.cc:3:21: error: expected primary-expression before ';' token
a.cc:3:21: error: expected ')' before ';' token
    3 | for(int ???=1;???<=9;???++)
      |    ~                ^
      |                     )
a.cc:3:22: error: expected primary-expression before '?' token
    3 | for(int ???=1;???<=9;???++)
      |                      ^
a.cc:3:23: error: expected primary-expression before '?' token
    3 | for(int ???=1;???<=9;???++)
      |                       ^
a.cc:3:24: error: expected primary-expression before '?' token
    3 | for(int ???=1;???<=9;???++)
      |                        ^
a.cc:3:27: error: expected primary-expression before ')' token
    3 | for(int ???=1;???<=9;???++)
      |                           ^
a.cc:3:27: error: expected ':' before ')' token
    3 | for(int ???=1;???<=9;???++)
      |                           ^
      |                           :
a.cc:3:27: error: expected primary-expression before ')' token
a.cc:3:27: error: expected ':' before ')' token
    3 | for(int ???=1;???<=9;???++)
      |                           ^
      |                           :
a.cc:3:27: error: expected primary-expression before ')' token
a.cc:3:27: error: expected ':' before ')' token
    3 | for(int ???=1;???<=9;???++)
      |                           ^
      |                           :
a.cc:3:27: error: expected primary-expression before ')' token
a.cc:4:15: error: expected primary-expression before '?' token
    4 | for(int ???=1;???<=9;???++)printf("%dx%d=%d\n",???,???,???*???);
      |               ^
a.cc:4:16: error: expected primary-expression before '?' token
    4 | for(int ???=1;???<=9;???++)printf("%dx%d=%d\n",???,???,???*???);
      |                ^
a.cc:4:17: error: expected primary-expression before '?' token
    4 | for(int ???=1;???<=9;???++)printf("%dx%d=%d\n",???,???,???*???);
      |                 ^
a.cc:4:18: error: expected primary-expression before '<=' token
    4 | for(int ???=1;???<=9;???++)printf("%dx%d=%d\n",???,???,???*???);
      |                  ^~
a.cc:4:21: error: expected ':' before ';' token
    4 | for(int ???=1;???<=9;???++)printf("%dx%d=%d\n",???,???,???*???);
      |                     ^
      |                     :
a.cc:4:21: error: expected primary-expression before ';' token
a.cc:4:21: error: expected ':' before ';' token
    4 | for(int ???=1;???<=9;???++)printf("%dx%d=%d\n",???,???,???*???);
      |                     ^
      |                     :
a.cc:4:21: error: expected primary-expression before ';' token
a.cc:4:21: error: expected ':' before ';' token
    4 | for(int ???=1;???<=9;???++)printf("%dx%d=%d\n",???,???,???*???);
      |                     ^
      |                     :
a.cc:4:21: error: expected primary-expression before ';' token
a.cc:4:22: error: expected primary-expression before '?' token
    4 | for(int ???=1;???<=9;???++)printf("%dx%d=%d\n",???,???,???*???);
      |                      ^
a.cc:4:23: error: expected primary-expression before '?' token
    4 | for(int ???=1;???<=9;???++)printf("%dx%d=%d\n",???,???,???*???);
      |                       ^
a.cc:4:24: error: expected primary-expression before '?' token
    4 | for(int ???=1;???<=9;???++)printf("%dx%d=%d\n",???,???,???*???);
      |                        ^
a.cc:4:27: error: expected primary-expression before ')' token
    4 | for(int ???=1;???<=9;???++)printf("%dx%d=%d\n",???,???,???*???);
      |                           ^
a.cc:4:27: error: expected ':' before ')' token
    4 | for(int ???=1;???<=9;???++)printf("%dx%d=%d\n",???,???,???*???);
      |                           ^
      |                           :
a.cc:4:27: error: expected primary-expression before ')' token
a.cc:4:27: error: expected ':' before ')' token
    4 | for(int ???=1;???<=9;???++)printf("%dx%d=%d\n",???,???,???*???);
      |                           ^
      |                           :
a.cc:4:27: error: expected primary-expression before ')' token
a.cc:4:27: error: expected ':' before ')' token
    4 | for(int ???=1;???<=9;???++)printf("%dx%d=%d\n",???,???,???*???);
      |                           ^
      |                           :
a.cc:4:27: error: expected primary-expression before ')' token