foo.c:2:15: error: expected expression before 'int'
 const int N = int(1e5) + 9;
               ^
foo.c:3:1: error: unknown type name 'string'
 string expr, name; VI I;
 ^
foo.c:3:20: error: unknown type name 'VI'
 string expr, name; VI I;
                    ^
foo.c: In function 'out':
foo.c:6:1: warning: implicit declaration of function 'SZ' [-Wimplicit-function-declaration]
 if (k == SZ(I)) cout << name; else{ printf("op(%d,",I[k]);out(k+1);printf(")"); } }
 ^
foo.c:6:17: error: 'cout' undeclared (first use in this function)
 if (k == SZ(I)) cout << name; else{ printf("op(%d,",I[k]);out(k+1);printf(")"); } }
                 ^
foo.c:6:17: note: each undeclared identifier is reported only once for each function it appears in
foo.c:6:1: warning: implicit declaration of function 'printf' [-Wimplicit-function-declaration]
 if (k == SZ(I)) cout << name; else{ printf("op(%d,",I[k]);out(k+1);printf(")"); } }
 ^
foo.c:6:37: warning: incompatible implicit declaration of built-in function 'printf' [enabled by default]
 if (k == SZ(I)) cout << name; else{ printf("op(%d,",I[k]);out(k+1);printf(")"); } }
                                     ^
foo.c:6:54: error: subscripted value is neither array nor pointer nor vector
 if (k == SZ(I)) cout << name; else{ printf("op(%d,",I[k]);out(k+1);printf(")"); } }
                                                      ^
foo.c: In function 'gao':
foo.c:10:1: warning: implicit declaration of function 'FOR' [-Wimplicit-function-declaration]
 if (k == SZ(I)){ FOR(i,l,r)putchar(expr[i]);puts(""); } else{
 ^
foo.c:10:22: error: 'i' undeclared (first use in this function)
 if (k == SZ(I)){ FOR(i,l,r)putchar(expr[i]);puts(""); } else{
                      ^
foo.c:10:28: error: expected ';' before 'putchar'
 if (k == SZ(I)){ FOR(i,l,r)putchar(expr[i]);puts(""); } else{
                            ^
foo.c:10:28: warning: implicit declaration of function 'puts' [-Wimplicit-function-declaration]
foo.c:11:32: error: unknown type name 'VII'
     int c=0;char op='(';int ll;VII cut;
                                ^
foo.c:12:16: error: expected ';' before 'if'
     FOR(i,l,r) if(expr[i]=='('){if (!c++)ll=i+1;}
                ^
foo.c:11:36: warning: unused variable 'cut' [-Wunused-variable]
     int c=0;char op='(';int ll;VII cut;
                                    ^
foo.c:11:29: warning: unused variable 'll' [-Wunused-variable]
     int c=0;char op='(';int ll;VII cut;
                             ^
foo.c:11:18: warning: unused variable 'op' [-Wunused-variable]
     int c=0;char op='(';int ll;VII cut;
                  ^
foo.c:11:9: warning: unused variable 'c' [-Wunused-variable]
     int c=0;char op='(';int ll;VII cut;
         ^
foo.c: In function 'main':
foo.c:33:1: error: unknown type name 'ifndef'
 ifndef ONLINE_JUDGE
 ^
foo.c:35:1: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'freopen'
 freopen("in.txt", "r", stdin);
 ^
foo.c:37:1: error: 'endif' undeclared (first use in this function)
 endif
 ^
foo.c:39:1: error: expected ';' before 'while'
 while (cin >> expr){
 ^
foo.c: At top level:
foo.c:49:3: error: expected identifier or '(' before '~' token
 } ~
   ^
foo.c: In function 'main':
foo.c:49:1: warning: control reaches end of non-void function [-Wreturn-type]
 } ~
 ^