stablegradients/pie-gem5-pairs huggingface dataset:
// Slower C++ solution:
#include <bits/stdc++.h>

using namespace std;

int main(){

    string s;

    cin >> s;

    if(s == "ABC") cout<<"ARC";

    else cout<<"ABC";

}

// Faster C++ solution for the same problem (measured speedup: 5.3386006549103255x):
#include <stdio.h>



int main(){

	char word[10];

	scanf("%s", word);

	

	if (word[1] == 'B') puts("ARC");

	else puts ("ABC");

	return 0;

}
// Slower C++ solution:
#include<iostream> 

#include<cstring>

#include<cstdio>

#include<string>

#include<cmath>

#include<algorithm>

#include<map>

#include <cstdlib>

using namespace std;



int main(){

	string s;

	cin>>s;

	if(s[1]=='B') cout<<"ARC";

	else cout<<"ABC";

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.376564424550125x):
#include <stdio.h>



int main(){

	char word[10];

	scanf("%s", word);

	

	if (word[1] == 'B') puts("ARC");

	else puts ("ABC");

	return 0;

}
// Slower C++ solution:
#include<iostream>

#include<cstring>

using namespace std;

int main ()

{

    char S[50];

    cin>>S;

    if (strcmp("ABC",S)==0)

    cout<<"ARC"<<endl;

    if (strcmp("ARC",S)==0)

    cout<<"ABC"<<endl;

    return 0;

}


// Faster C++ solution for the same problem (measured speedup: 5.349526842310812x):
#include <stdio.h>



int main(){

	char word[10];

	scanf("%s", word);

	

	if (word[1] == 'B') puts("ARC");

	else puts ("ABC");

	return 0;

}
// Slower C++ solution:
#include <iostream>

using namespace std;

int main() {

    string ss;

    cin>>ss;

    if(ss[1]=='R'){

    	cout<<"ABC";

    }else cout<<"ARC";

    return 0;

}


// Faster C++ solution for the same problem (measured speedup: 5.374481028629796x):
#include <stdio.h>



int main(){

	char word[10];

	scanf("%s", word);

	

	if (word[1] == 'B') puts("ARC");

	else puts ("ABC");

	return 0;

}
// Slower C++ solution:
#include<iostream>

using namespace std;

int main()

{

    string S;

    cin>>S;

    if(S=="ABC")

        cout<<"ARC";

    else

        cout<<"ABC";

}


// Faster C++ solution for the same problem (measured speedup: 5.3386006549103255x):
#include <stdio.h>



int main(){

	char word[10];

	scanf("%s", word);

	

	if (word[1] == 'B') puts("ARC");

	else puts ("ABC");

	return 0;

}
// Slower C++ solution:
#include <iostream>

using namespace std;

int main(){



    string S;

    cin>> S;



    if(S == "ABC"){

        cout<< "ARC";

    }

    else{

        cout<< "ABC";

    }



    return 0;

}


// Faster C++ solution for the same problem (measured speedup: 5.318468859425972x):
#include <stdio.h>



int main (){

	char a[5];

	

	scanf ("%s",a);

	

	if (a[1]=='B'){

		printf ("ARC\n");

	}

	else {

		printf ("ABC\n");

	}

	return 0;

}
// Slower C++ solution:
#include <bits/stdc++.h>

using namespace std;

int main(){

    string s;

    cin >> s;

    if(s == "ABC") cout<<"ARC";

    else cout<<"ABC";

}

// Faster C++ solution for the same problem (measured speedup: 5.318468859425972x):
#include <stdio.h>



int main (){

	char a[5];

	

	scanf ("%s",a);

	

	if (a[1]=='B'){

		printf ("ARC\n");

	}

	else {

		printf ("ABC\n");

	}

	return 0;

}
// Slower C++ solution:
#include<iostream> 

#include<cstring>

#include<cstdio>

#include<string>

#include<cmath>

#include<algorithm>

#include<map>

#include <cstdlib>

using namespace std;



int main(){

	string s;

	cin>>s;

	if(s[1]=='B') cout<<"ARC";

	else cout<<"ABC";

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.356289468171071x):
#include <stdio.h>



int main (){

	char a[5];

	

	scanf ("%s",a);

	

	if (a[1]=='B'){

		printf ("ARC\n");

	}

	else {

		printf ("ABC\n");

	}

	return 0;

}
// Slower C++ solution:
#include<iostream>

#include<cstring>

using namespace std;

int main ()

{

    char S[50];

    cin>>S;

    if (strcmp("ABC",S)==0)

    cout<<"ARC"<<endl;

    if (strcmp("ARC",S)==0)

    cout<<"ABC"<<endl;

    return 0;

}


// Faster C++ solution for the same problem (measured speedup: 5.329353844312094x):
#include <stdio.h>



int main (){

	char a[5];

	

	scanf ("%s",a);

	

	if (a[1]=='B'){

		printf ("ARC\n");

	}

	else {

		printf ("ABC\n");

	}

	return 0;

}
// Slower C++ solution:
#include <iostream>

using namespace std;

int main() {

    string ss;

    cin>>ss;

    if(ss[1]=='R'){

    	cout<<"ABC";

    }else cout<<"ARC";

    return 0;

}


// Faster C++ solution for the same problem (measured speedup: 5.354213928710382x):
#include <stdio.h>



int main (){

	char a[5];

	

	scanf ("%s",a);

	

	if (a[1]=='B'){

		printf ("ARC\n");

	}

	else {

		printf ("ABC\n");

	}

	return 0;

}
// Slower C++ solution:
#include<iostream>

using namespace std;

int main()

{

    string S;

    cin>>S;

    if(S=="ABC")

        cout<<"ARC";

    else

        cout<<"ABC";

}


// Faster C++ solution for the same problem (measured speedup: 5.318468859425972x):
#include <stdio.h>



int main (){

	char a[5];

	

	scanf ("%s",a);

	

	if (a[1]=='B'){

		printf ("ARC\n");

	}

	else {

		printf ("ABC\n");

	}

	return 0;

}
// Slower C++ solution:
#include <iostream>

using namespace std;

int main(){



    string S;

    cin>> S;



    if(S == "ABC"){

        cout<< "ARC";

    }

    else{

        cout<< "ABC";

    }



    return 0;

}


// Faster C++ solution for the same problem (measured speedup: 5.295583090465889x):
//Given a string S representing the type of the contest held last week

//print the string representing the type of the contest held this week.



#include <stdio.h>



int main ()

{

	char S[5];

	scanf("%s", &S);

	

	if(S[1]=='B')

	{

		S[1]='R';

		printf("%s",S);

	}

	

	else if (S[1]=='R')

	{

		S[1]='B';

		printf("%s",S);	

	}

	

	return 0;

}
// Slower C++ solution:
#include <bits/stdc++.h>

using namespace std;

int main(){

    string s;

    cin >> s;

    if(s == "ABC") cout<<"ARC";

    else cout<<"ABC";

}

// Faster C++ solution for the same problem (measured speedup: 5.295583090465889x):
//Given a string S representing the type of the contest held last week

//print the string representing the type of the contest held this week.



#include <stdio.h>



int main ()

{

	char S[5];

	scanf("%s", &S);

	

	if(S[1]=='B')

	{

		S[1]='R';

		printf("%s",S);

	}

	

	else if (S[1]=='R')

	{

		S[1]='B';

		printf("%s",S);	

	}

	

	return 0;

}
// Slower C++ solution:
#include<iostream> 

#include<cstring>

#include<cstdio>

#include<string>

#include<cmath>

#include<algorithm>

#include<map>

#include <cstdlib>

using namespace std;



int main(){

	string s;

	cin>>s;

	if(s[1]=='B') cout<<"ARC";

	else cout<<"ABC";

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.333240954305161x):
//Given a string S representing the type of the contest held last week

//print the string representing the type of the contest held this week.



#include <stdio.h>



int main ()

{

	char S[5];

	scanf("%s", &S);

	

	if(S[1]=='B')

	{

		S[1]='R';

		printf("%s",S);

	}

	

	else if (S[1]=='R')

	{

		S[1]='B';

		printf("%s",S);	

	}

	

	return 0;

}
// Slower C++ solution:
#include<iostream>

#include<cstring>

using namespace std;

int main ()

{

    char S[50];

    cin>>S;

    if (strcmp("ABC",S)==0)

    cout<<"ARC"<<endl;

    if (strcmp("ARC",S)==0)

    cout<<"ABC"<<endl;

    return 0;

}


// Faster C++ solution for the same problem (measured speedup: 5.3064212364485925x):
//Given a string S representing the type of the contest held last week

//print the string representing the type of the contest held this week.



#include <stdio.h>



int main ()

{

	char S[5];

	scanf("%s", &S);

	

	if(S[1]=='B')

	{

		S[1]='R';

		printf("%s",S);

	}

	

	else if (S[1]=='R')

	{

		S[1]='B';

		printf("%s",S);	

	}

	

	return 0;

}
// Slower C++ solution:
#include <iostream>

using namespace std;

int main() {

    string ss;

    cin>>ss;

    if(ss[1]=='R'){

    	cout<<"ABC";

    }else cout<<"ARC";

    return 0;

}


// Faster C++ solution for the same problem (measured speedup: 5.33117434604588x):
//Given a string S representing the type of the contest held last week

//print the string representing the type of the contest held this week.



#include <stdio.h>



int main ()

{

	char S[5];

	scanf("%s", &S);

	

	if(S[1]=='B')

	{

		S[1]='R';

		printf("%s",S);

	}

	

	else if (S[1]=='R')

	{

		S[1]='B';

		printf("%s",S);	

	}

	

	return 0;

}
// Slower C++ solution:
#include<iostream>

using namespace std;

int main()

{

    string S;

    cin>>S;

    if(S=="ABC")

        cout<<"ARC";

    else

        cout<<"ABC";

}


// Faster C++ solution for the same problem (measured speedup: 5.295583090465889x):
//Given a string S representing the type of the contest held last week

//print the string representing the type of the contest held this week.



#include <stdio.h>



int main ()

{

	char S[5];

	scanf("%s", &S);

	

	if(S[1]=='B')

	{

		S[1]='R';

		printf("%s",S);

	}

	

	else if (S[1]=='R')

	{

		S[1]='B';

		printf("%s",S);	

	}

	

	return 0;

}
// Slower C++ solution:
#include <iostream>

using namespace std;

int main(){



    string S;

    cin>> S;



    if(S == "ABC"){

        cout<< "ARC";

    }

    else{

        cout<< "ABC";

    }



    return 0;

}


// Faster C++ solution for the same problem (measured speedup: 5.318468859425972x):
#include <stdio.h>

int main(){

    char input[5];

    scanf("%s", input);

    switch (input[1])

    {

        case 'B':

        printf("ARC\n");

        break;

        case 'R':

        printf("ABC\n");

        break;

    }

    return 0;

}
// Slower C++ solution:
#include <bits/stdc++.h>

using namespace std;

int main(){

    string s;

    cin >> s;

    if(s == "ABC") cout<<"ARC";

    else cout<<"ABC";

}

// Faster C++ solution for the same problem (measured speedup: 5.318468859425972x):
#include <stdio.h>

int main(){

    char input[5];

    scanf("%s", input);

    switch (input[1])

    {

        case 'B':

        printf("ARC\n");

        break;

        case 'R':

        printf("ABC\n");

        break;

    }

    return 0;

}
// Slower C++ solution:
#include<iostream> 

#include<cstring>

#include<cstdio>

#include<string>

#include<cmath>

#include<algorithm>

#include<map>

#include <cstdlib>

using namespace std;



int main(){

	string s;

	cin>>s;

	if(s[1]=='B') cout<<"ARC";

	else cout<<"ABC";

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.356289468171071x):
#include <stdio.h>

int main(){

    char input[5];

    scanf("%s", input);

    switch (input[1])

    {

        case 'B':

        printf("ARC\n");

        break;

        case 'R':

        printf("ABC\n");

        break;

    }

    return 0;

}
// Slower C++ solution:
#include<iostream>

#include<cstring>

using namespace std;

int main ()

{

    char S[50];

    cin>>S;

    if (strcmp("ABC",S)==0)

    cout<<"ARC"<<endl;

    if (strcmp("ARC",S)==0)

    cout<<"ABC"<<endl;

    return 0;

}


// Faster C++ solution for the same problem (measured speedup: 5.329353844312094x):
#include <stdio.h>

int main(){

    char input[5];

    scanf("%s", input);

    switch (input[1])

    {

        case 'B':

        printf("ARC\n");

        break;

        case 'R':

        printf("ABC\n");

        break;

    }

    return 0;

}
// Slower C++ solution:
#include <iostream>

using namespace std;

int main() {

    string ss;

    cin>>ss;

    if(ss[1]=='R'){

    	cout<<"ABC";

    }else cout<<"ARC";

    return 0;

}


// Faster C++ solution for the same problem (measured speedup: 5.354213928710382x):
#include <stdio.h>

int main(){

    char input[5];

    scanf("%s", input);

    switch (input[1])

    {

        case 'B':

        printf("ARC\n");

        break;

        case 'R':

        printf("ABC\n");

        break;

    }

    return 0;

}
// Slower C++ solution:
#include<iostream>

using namespace std;

int main()

{

    string S;

    cin>>S;

    if(S=="ABC")

        cout<<"ARC";

    else

        cout<<"ABC";

}


// Faster C++ solution for the same problem (measured speedup: 5.318468859425972x):
#include <stdio.h>

int main(){

    char input[5];

    scanf("%s", input);

    switch (input[1])

    {

        case 'B':

        printf("ARC\n");

        break;

        case 'R':

        printf("ABC\n");

        break;

    }

    return 0;

}
// Slower C++ solution:
#include <iostream>

using namespace std;

int main(){



    string S;

    cin>> S;



    if(S == "ABC"){

        cout<< "ARC";

    }

    else{

        cout<< "ABC";

    }



    return 0;

}


// Faster C++ solution for the same problem (measured speedup: 5.321351463846276x):
#include<stdio.h>

#include<string.h>



int main(){

	char idk[4];

	scanf("%s",idk);

	strcmp(idk,"ABC")==0?printf("ARC\n") : printf("ABC\n");

	return 0;

}
// Slower C++ solution:
#include <bits/stdc++.h>

using namespace std;

int main(){

    string s;

    cin >> s;

    if(s == "ABC") cout<<"ARC";

    else cout<<"ABC";

}

// Faster C++ solution for the same problem (measured speedup: 5.321351463846276x):
#include<stdio.h>

#include<string.h>



int main(){

	char idk[4];

	scanf("%s",idk);

	strcmp(idk,"ABC")==0?printf("ARC\n") : printf("ABC\n");

	return 0;

}
// Slower C++ solution:
#include<iostream> 

#include<cstring>

#include<cstdio>

#include<string>

#include<cmath>

#include<algorithm>

#include<map>

#include <cstdlib>

using namespace std;



int main(){

	string s;

	cin>>s;

	if(s[1]=='B') cout<<"ARC";

	else cout<<"ABC";

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.35919257132077x):
#include<stdio.h>

#include<string.h>



int main(){

	char idk[4];

	scanf("%s",idk);

	strcmp(idk,"ABC")==0?printf("ARC\n") : printf("ABC\n");

	return 0;

}
// Slower C++ solution:
#include<iostream>

#include<cstring>

using namespace std;

int main ()

{

    char S[50];

    cin>>S;

    if (strcmp("ABC",S)==0)

    cout<<"ARC"<<endl;

    if (strcmp("ARC",S)==0)

    cout<<"ABC"<<endl;

    return 0;

}


// Faster C++ solution for the same problem (measured speedup: 5.332242348382538x):
#include<stdio.h>

#include<string.h>



int main(){

	char idk[4];

	scanf("%s",idk);

	strcmp(idk,"ABC")==0?printf("ARC\n") : printf("ABC\n");

	return 0;

}
// Slower C++ solution:
#include <iostream>

using namespace std;

int main() {

    string ss;

    cin>>ss;

    if(ss[1]=='R'){

    	cout<<"ABC";

    }else cout<<"ARC";

    return 0;

}


// Faster C++ solution for the same problem (measured speedup: 5.357115906919919x):
#include<stdio.h>

#include<string.h>



int main(){

	char idk[4];

	scanf("%s",idk);

	strcmp(idk,"ABC")==0?printf("ARC\n") : printf("ABC\n");

	return 0;

}
// Slower C++ solution:
#include<iostream>

using namespace std;

int main()

{

    string S;

    cin>>S;

    if(S=="ABC")

        cout<<"ARC";

    else

        cout<<"ABC";

}


// Faster C++ solution for the same problem (measured speedup: 5.321351463846276x):
#include<stdio.h>

#include<string.h>



int main(){

	char idk[4];

	scanf("%s",idk);

	strcmp(idk,"ABC")==0?printf("ARC\n") : printf("ABC\n");

	return 0;

}
// Slower C++ solution:
#include <iostream>

#include <string>



int main() {

	std::string str;

	std::cin >> str;



	if (str == "ABC")

		std::cout << "ARC";

	else

		std::cout << "ABC";

}

// Faster C++ solution for the same problem (measured speedup: 5.321351463846276x):
#include<stdio.h>

#include<string.h>



int main(){

	char idk[4];

	scanf("%s",idk);

	strcmp(idk,"ABC")==0?printf("ARC\n") : printf("ABC\n");

	return 0;

}
// Slower C++ solution:
#include <iostream>

using namespace std;

int main(){



    string S;

    cin>> S;



    if(S == "ABC"){

        cout<< "ARC";

    }

    else{

        cout<< "ABC";

    }



    return 0;

}


// Faster C++ solution for the same problem (measured speedup: 5.322267862464304x):
#include <stdio.h>



int main(){

	char str[5];

	

	scanf("%s", &str);

	

	str[1]=='R'?printf("ABC"):printf("ARC");



	return 0;

}
// Slower C++ solution:
#include <bits/stdc++.h>

using namespace std;

int main(){

    string s;

    cin >> s;

    if(s == "ABC") cout<<"ARC";

    else cout<<"ABC";

}

// Faster C++ solution for the same problem (measured speedup: 5.322267862464304x):
#include <stdio.h>



int main(){

	char str[5];

	

	scanf("%s", &str);

	

	str[1]=='R'?printf("ABC"):printf("ARC");



	return 0;

}
// Slower C++ solution:
#include<iostream> 

#include<cstring>

#include<cstdio>

#include<string>

#include<cmath>

#include<algorithm>

#include<map>

#include <cstdlib>

using namespace std;



int main(){

	string s;

	cin>>s;

	if(s[1]=='B') cout<<"ARC";

	else cout<<"ABC";

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.360115486617659x):
#include <stdio.h>



int main(){

	char str[5];

	

	scanf("%s", &str);

	

	str[1]=='R'?printf("ABC"):printf("ARC");



	return 0;

}
// Slower C++ solution:
#include<iostream>

#include<cstring>

using namespace std;

int main ()

{

    char S[50];

    cin>>S;

    if (strcmp("ABC",S)==0)

    cout<<"ARC"<<endl;

    if (strcmp("ARC",S)==0)

    cout<<"ABC"<<endl;

    return 0;

}


// Faster C++ solution for the same problem (measured speedup: 5.3331606225375605x):
#include <stdio.h>



int main(){

	char str[5];

	

	scanf("%s", &str);

	

	str[1]=='R'?printf("ABC"):printf("ARC");



	return 0;

}
// Slower C++ solution:
#include <iostream>

using namespace std;

int main() {

    string ss;

    cin>>ss;

    if(ss[1]=='R'){

    	cout<<"ABC";

    }else cout<<"ARC";

    return 0;

}


// Faster C++ solution for the same problem (measured speedup: 5.358038464591043x):
#include <stdio.h>



int main(){

	char str[5];

	

	scanf("%s", &str);

	

	str[1]=='R'?printf("ABC"):printf("ARC");



	return 0;

}
// Slower C++ solution:
#include<iostream>

using namespace std;

int main()

{

    string S;

    cin>>S;

    if(S=="ABC")

        cout<<"ARC";

    else

        cout<<"ABC";

}


// Faster C++ solution for the same problem (measured speedup: 5.322267862464304x):
#include <stdio.h>



int main(){

	char str[5];

	

	scanf("%s", &str);

	

	str[1]=='R'?printf("ABC"):printf("ARC");



	return 0;

}
// Slower C++ solution:
#include <iostream>

#include <string>



int main() {

	std::string str;

	std::cin >> str;



	if (str == "ABC")

		std::cout << "ARC";

	else

		std::cout << "ABC";

}

// Faster C++ solution for the same problem (measured speedup: 5.322267862464304x):
#include <stdio.h>



int main(){

	char str[5];

	

	scanf("%s", &str);

	

	str[1]=='R'?printf("ABC"):printf("ARC");



	return 0;

}
// Slower C++ solution:


#include <bits/stdc++.h>

#include<algorithm>

#include<cstring>

#include<cmath>

#include<cstdlib>

#include<string.h>

using namespace std;

#define pb push_back

#define all(v) v. begin(),v. end()

#define  rep(i,n,v) for(i=n;i<v;i++)

#define per(i,n,v) for(i=n;i>v;i--)

#define ff first 

#define ss second 

#define pp pair<ll,ll>

#define ll  long long

#define endl '\n'

void solve()

{

  ll n, a,m=0,b=1, c,k=0, i, j,l=1e9+7;

  string s, r, y;

  cin>>s;

  if(s[1]=='B') cout<<"ARC";

  else cout<<"ABC";

}

int main()

{

 ios_base::sync_with_stdio(false);

  cin. tie(0);cout. tie(0);

    ll t=1;

  // cin>>t;

    while(t--)

    {

      solve();

    }

    return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.438850644595624x):
#include <stdio.h>



int main(){

	char str[5];

	

	scanf("%s", &str);

	

	str[1]=='R'?printf("ABC"):printf("ARC");



	return 0;

}
// Slower C++ solution:
#include<bits/stdc++.h>

using namespace std;

int main()

{

    string s;

    cin>>s;

    if(s=="ABC")cout<<"ARC"<<endl;

    else if(s=="ARC")cout<<"ABC"<<endl;

    return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.3324347060725446x):
#include <stdio.h>

#include <string.h>



int main(){

	char S[100];

	scanf("%s", &S);

	if(strcmp(S, "ABC") == 0){

		printf("ARC\n");

	}

	if(strcmp(S, "ARC") == 0){

		printf("ABC\n");

	}

	return 0;

}
// Slower C++ solution:
#include<iostream>

using namespace std;

int main(){

     string a;cin>>a;

     if(a=="ABC") cout<<"ARC";

     else cout<<"ABC";

}

// Faster C++ solution for the same problem (measured speedup: 5.320092926341505x):
#include <stdio.h>

#include <string.h>



int main(){

	char S[100];

	scanf("%s", &S);

	if(strcmp(S, "ABC") == 0){

		printf("ARC\n");

	}

	if(strcmp(S, "ARC") == 0){

		printf("ABC\n");

	}

	return 0;

}
// Slower C++ solution:
#include<iostream>

using namespace std;

int main()

{

	string s;

	cin>>s;

	if(s[1]=='B')cout<<"ARC";

	if(s[1]=='R')cout<<"ABC";

}

// Faster C++ solution for the same problem (measured speedup: 5.315097836109548x):
#include <stdio.h>

#include <string.h>



int main(){

	char S[100];

	scanf("%s", &S);

	if(strcmp(S, "ABC") == 0){

		printf("ARC\n");

	}

	if(strcmp(S, "ARC") == 0){

		printf("ABC\n");

	}

	return 0;

}
// Slower C++ solution:
#include<iostream>

#include<cmath>

#include<stack>

#include<vector>

#include<cstring>

#include<algorithm>

#include<set>

#include<queue>

#include <vector>

#include <list>

#include <map>

#include <set>

#include <deque>

#include <stack>

#include <bitset>

#include <algorithm>

#include <functional>

#include <numeric>

#include <utility>

#include <complex>

#include <sstream>

#include <iomanip>

#include <cstdio>

#include <cmath>

#include <cstdlib>

#include <cstring>

#include <ctime>

#include <cassert>

using namespace std;

typedef long long ll;

typedef unsigned long long ull;

const int inf =0x3f3f3f3f;

#define scn(a) scanf("%d",&a)

#define scd(a) scanf("%lf",&a)

#define scl(a) scanf("%lld",&a)

#define ptf(a) printf("%d\n",a)

#define mes(a,b) memset(a,b,sizeof(a))

#define fon(s,n) for(int i=s;i<=n;i++)

#define range(i,a,b) for(int i=a;i<=b;++i)

#define rerange(i,a,b) for(int i=a;i>=b;--i)

#define maxn 1000010

const int S=20;

ll gcd(ll a,ll b) { return b>0 ? gcd(b,a%b):a;}

ll lcm(ll a,ll b){return a*b/gcd(a,b);}

ll q_pow(ll a,ll b,ll mod)

{

	ll ans=1,res=a;

	while(b){

		if(b&1) ans=ans*res%mod;

		res=res*res%mod;

		b>>=1;

	}

	return ans%mod;

}



int month[13]={0,31,28,31,30,31,30,31,31,30,31,30,31};

int main()

{

    string a="ARC",b="ABC";

    string temp;

    cin>>temp;

    if(temp==a) cout<<b<<endl;

    else cout<<a<<endl;



    return 0;

}


// Faster C++ solution for the same problem (measured speedup: 5.326801944747147x):
#include <stdio.h>

#include <string.h>



int main(){

	char S[100];

	scanf("%s", &S);

	if(strcmp(S, "ABC") == 0){

		printf("ARC\n");

	}

	if(strcmp(S, "ARC") == 0){

		printf("ABC\n");

	}

	return 0;

}