Main.cc: In function ‘int main()’:
Main.cc:12:9: error: ‘a’ was not declared in this scope
a[i] = c;
^
Main.cc:15:12: error: ‘a’ was not declared in this scope
if(a[i]=='a' && a[i+1]=='?')
^
Main.cc:17:12: error: ‘a’ was not declared in this scope
if(a[i]=='b' && a[i+1]=='?')
^
Main.cc:19:9: error: ‘a’ was not declared in this scope
if(a[i]=='a' && a[i+1]=='a')
^
Main.cc:7:17: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
int n; scanf("%d", &n);
~~~~~^~~~~~~~~~
Main.cc:11:14: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
scanf("%c", &c);
~~~~~^~~~~~~~~~