Language: C++

#include<iostream>
#include<algorithm>//sort(昇順)
#include<string>//F.size();文字列のサイズ
#include<cstdio>
#include<iomanip>
#include<vector>
#include<bits/stdc++.h>
#include<stack>
#include<queue>
#include<cmath>
#include<limits>
#include<map>


#define REP(i, n) for (int i = 0; i < n; i++)
#define FOR(i, a, b) for (int i = a; i < b; i++)

using namespace std;

int main(){
	int a,b,c=0,d=0;
	string s,t,l;
	cin >> s >> t;
	bool m[s.size];
	
	if(s.size<t.size){cout << "UNRESTORABLE" << endl;return 0;}
	
	REP(i,s.size){
		m[i]=true;
		if(s[i]=="?")
			m[i]=false;
		}
	}
	REP(i,s.size){
		if(m[i]==false){
			c++;
			if(c==t.size){
				d++;
				FOR(j,i-c,i)s[i]=t[i];
				break;
			}
		}else c=0;
	}
	REP(i,s.size){
		if(m[i]==false){
			s[i] = "a";
		}
	}
	if(d<1){cout << "UNRESTORABLE" << endl;return 0;}
	cout << s << endl;
	
return 0;}

Compiler output:
a.cc: In function 'int main()':
a.cc:24:22: error: cannot convert 'std::__cxx11::basic_string<char>::size' from type 'std::__cxx11::basic_string<char>::size_type (std::__cxx11::basic_string<char>::)() const noexcept' {aka 'long unsigned int (std::__cxx11::basic_string<char>::)() const noexcept'} to type 'long unsigned int'
   24 |         bool m[s.size];
      |                      ^
a.cc:24:18: error: size of array 'm' has non-integral type '<unresolved overloaded function type>'
   24 |         bool m[s.size];
      |                ~~^~~~
a.cc:26:14: error: invalid use of member function 'std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::size_type std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::size() const [with _CharT = char; _Traits = std::char_traits<char>; _Alloc = std::allocator<char>; size_type = long unsigned int]' (did you forget the '()' ?)
   26 |         if(s.size<t.size){cout << "UNRESTORABLE" << endl;return 0;}
      |            ~~^~~~
      |                  ()
a.cc:26:21: error: invalid use of member function 'std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::size_type std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::size() const [with _CharT = char; _Traits = std::char_traits<char>; _Alloc = std::allocator<char>; size_type = long unsigned int]' (did you forget the '()' ?)
   26 |         if(s.size<t.size){cout << "UNRESTORABLE" << endl;return 0;}
      |                   ~~^~~~
      |                         ()
a.cc:28:17: error: invalid use of member function 'std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::size_type std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::size() const [with _CharT = char; _Traits = std::char_traits<char>; _Alloc = std::allocator<char>; size_type = long unsigned int]' (did you forget the '()' ?)
   28 |         REP(i,s.size){
      |               ~~^~~~
a.cc:15:39: note: in definition of macro 'REP'
   15 | #define REP(i, n) for (int i = 0; i < n; i++)
      |                                       ^
a.cc:30:24: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   30 |                 if(s[i]=="?")
a.cc: At global scope:
a.cc:15:19: error: expected unqualified-id before 'for'
   15 | #define REP(i, n) for (int i = 0; i < n; i++)
      |                   ^~~
a.cc:34:9: note: in expansion of macro 'REP'
   34 |         REP(i,s.size){
      |         ^~~
a.cc:34:13: error: 'i' does not name a type
   34 |         REP(i,s.size){
      |             ^
a.cc:15:35: note: in definition of macro 'REP'
   15 | #define REP(i, n) for (int i = 0; i < n; i++)
      |                                   ^
a.cc:34:13: error: 'i' does not name a type
   34 |         REP(i,s.size){
      |             ^
a.cc:15:42: note: in definition of macro 'REP'
   15 | #define REP(i, n) for (int i = 0; i < n; i++)
      |                                          ^
a.cc:15:19: error: expected unqualified-id before 'for'
   15 | #define REP(i, n) for (int i = 0; i < n; i++)
      |                   ^~~
a.cc:44:9: note: in expansion of macro 'REP'
   44 |         REP(i,s.size){
      |         ^~~
a.cc:44:13: error: 'i' does not name a type
   44 |         REP(i,s.size){
      |             ^
a.cc:15:35: note: in definition of macro 'REP'
   15 | #define REP(i, n) for (int i = 0; i < n; i++)
      |                                   ^
a.cc:44:13: error: 'i' does not name a type
   44 |         REP(i,s.size){
      |             ^
a.cc:15:42: note: in definition of macro 'REP'
   15 | #define REP(i, n) for (int i = 0; i < n; i++)
      |                                          ^
a.cc:49:9: error: expected unqualified-id before 'if'
   49 |         if(d<1){cout << "UNRESTORABLE" << endl;return 0;}
      |         ^~
a.cc:50:9: error: 'cout' does not name a type
   50 |         cout << s << endl;
      |         ^~~~
a.cc:52:1: error: expected unqualified-id before 'return'
   52 | return 0;}
      | ^~~~~~
a.cc:52:10: error: expected declaration before '}' token
   52 | return 0;}
      |          ^