foo.cc:28:1: error: extended character 。 is not valid in an identifier
   28 | 找到规律之后，一看是斐波那契。
      | ^
foo.cc: In function 'int main()':
foo.cc:9:20: warning: unused variable 'p' [-Wunused-variable]
    9 | long long int i, j,p;
      |                    ^
foo.cc: At global scope:
foo.cc:28:1: error: '\U0000627e\U00005230\U000089c4\U00005f8b\U00004e4b\U0000540e\U0000ff0c\U00004e00\U0000770b\U0000662f\U00006590\U00006ce2\U000090a3\U00005951\U00003002' does not name a type
   28 | 找到规律之后，一看是斐波那契。
      | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:34:5: error: redefinition of 'int main()'
   34 | int main(){
      |     ^~~~
foo.cc:6:5: note: 'int main()' previously defined here
    6 | int main(){
      |     ^~~~

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