foo.cc: In function 'int main()':
foo.cc:12:28: error: expected primary-expression before '[' token
   12 |         tempi = atoi(string[flag+1])*atoi(string[flag-1]);
      |                            ^
foo.cc:12:49: error: expected primary-expression before '[' token
   12 |         tempi = atoi(string[flag+1])*atoi(string[flag-1]);
      |                                                 ^
foo.cc:18:28: error: expected primary-expression before '[' token
   18 |         tempi = atoi(string[flag+1])+atoi(string[flag-1]);
      |                            ^
foo.cc:18:49: error: expected primary-expression before '[' token
   18 |         tempi = atoi(string[flag+1])+atoi(string[flag-1]);
      |                                                 ^
foo.cc:23:5: error: expected ',' or ';' before 'cout'
   23 |     cout<<com[len-4]<<com[len-3]<<com[len-2]<<com[len-1];
      |     ^~~~
foo.cc:22:9: warning: unused variable 'len' [-Wunused-variable]
   22 |     int len = com.length()
      |         ^~~

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