foo.cpp:8:26: error: 'maxn' was not declared in this scope
 long int n,a,b,c,x,f,ans[maxn];
                          ^
foo.cpp: In function 'int main()':
foo.cpp:18:1: error: 'endif' was not declared in this scope
 endif
 ^
foo.cpp:19:1: error: expected ';' before 'scanf'
 scanf("%d%d",&n,&c);
 ^
foo.cpp:20:35: error: 'ans' was not declared in this scope
 for (int i=1;i<n;i++) scanf("%d",&ans[i]);
                                   ^
foo.cpp:25:26: error: 'ans' was not declared in this scope
 if (go||((long long int) ans[c]*a+b)%c==ans[c+1])
                          ^
foo.cpp:40:34: warning: format '%d' expects argument of type 'int', but argument 2 has type 'long int' [-Wformat=]
         printf("%d %d %d\n",x,a,b);
                                  ^
foo.cpp:40:34: warning: format '%d' expects argument of type 'int', but argument 3 has type 'long int' [-Wformat=]
foo.cpp:40:34: warning: format '%d' expects argument of type 'int', but argument 4 has type 'long int' [-Wformat=]