Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
	"strings"
)

func main() {
	io := NewIo()
	defer io.Flush()
	n := io.NextInt()
	for i := 0; i < n; i++ {
		s, t := io.NextLine(), io.NextLine()
		io.Println(f(s, t))
	}
}

func f(s, t string) string {
	for i := len(s) - 1; i >= 0; i-- {
		switch s[i] {
		case 'C':
			t = strings.Join([]string{t[1:], string(t[0])}, "")
		case 'J':
			t = strings.Join([]string{string(t[len(t)-1]), t[:len(t)-1]}, "")
		case 'E':
			if len(t)%2 == 1 {
				t = strings.Join([]string{t[len(t)/2+1:], string(t[len(t)/2]), t[:len(t)/2]}, "")
			} else {
				t = strings.Join([]string{t[len(t)/2:], t[:len(t)/2]}, "")
			}
		case 'A':
			r := []rune(t)
			for i, n := 0, len(r); i < n/2; i++ {
				r[i], r[n-i-1] = r[n-i-1], r[i]
			}
			t = string(r)
		case 'M':
			r := []rune(t)
			for i := 0; i < len(r); i++ {
				if '0' <= r[i] && r[i] < '9' {
					r[i]++
				} else if r[i] == '9' {
					r[i] = '0'
				}
			}
			t = string(r)
		case 'P':
			r := []rune(t)
			for i := 0; i < len(r); i++ {
				if '0' < r[i] && r[i] <= '9' {
					r[i]--
				} else if r[i] == '0' {
					r[i] = '9'
				}
			}
			t = string(r)
		}
	}
	return t
}

// I/O template
type Io struct {
	reader    *bufio.Reader
	writer    *bufio.Writer
	tokens    []string
	nextToken int
}

func NewIo() *Io {
	return &Io{
		reader: bufio.NewReader(os.Stdin),
		writer: bufio.NewWriter(os.Stdout),
	}
}

func (io *Io) Flush() {
	err := io.writer.Flush()
	if err != nil {
		panic(err)
	}
}

func (io *Io) NextLine() string {
	var buff []byte
	for {
		line, isPrefix, err := io.reader.ReadLine()
		if err != nil {
			panic(err)
		}
		buff = append(buff, line...)
		if !isPrefix {
			break
		}
	}
	return string(buff)
}

func (io *Io) Next() string {
	for io.nextToken >= len(io.tokens) {
		line := io.NextLine()
		io.tokens = strings.Fields(line)
		io.nextToken = 0
	}
	s := io.tokens[io.nextToken]
	io.nextToken++
	return s
}

func (io *Io) NextInt() int {
	i, err := strconv.Atoi(io.Next())
	if err != nil {
		panic(err)
	}
	return i
}

func (io *Io) NextFloat() float64 {
	i, err := strconv.ParseFloat(io.Next(), 64)
	if err != nil {
		panic(err)
	}
	return i
}

func (io *Io) Println(a ...interface{}) {
	fmt.Fprintln(io.writer, a...)
}

func (io *Io) Printf(format string, a ...interface{}) {
	fmt.Fprintf(io.writer, format, a...)
}

func (io *Io) PrintIntSlice(a []int) {
	b := make([]interface{}, 0, len(a))
	for _, x := range a {
		b = append(b, x)
	}
	io.Println(b...)
}

func (io *Io) PrintStringSlice(a []string) {
	b := make([]interface{}, 0, len(a))
	for _, x := range a {
		b = append(b, x)
	}
	io.Println(b...)
}

func Log(name string, value interface{}) {
	fmt.Fprintf(os.Stderr, "%s=%+v\n", name, value)
}

func ExampleIo() {
	io := NewIo()
	defer io.Flush()
	a := make([]int, 0, 3)
	a[0], a[1], a[2] = io.NextInt(), io.NextInt(), io.NextInt()
	io.Println(a)
	io.PrintIntSlice(a)
	Log("io", a)
}

C++: #include <iostream>
#include <sstream>
#include <string>
#include <algorithm>
#include <vector>
#include <stack>
#include <queue>
#include <set>
#include <map>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <cassert>

using namespace std;

#define FOR(i,k,n) for(int i=(k); i<(int)n; ++i)
#define REP(i,n) FOR(i,0,n)
#define FORIT(i,c) for(__typeof((c).begin())i=(c).begin();i!=(c).end();++i)

template<class T> void debug(T begin, T end){ for(T i = begin; i != end; ++i) cout<<*i<<" "; cout<<endl; }

typedef long long ll;
const int INF = 100000000;
const double EPS = 1e-8;
const int MOD = 1000000007;

int main(){
  int n;
  cin>>n;
  while(n--){
    string s,t;
    cin>>s>>t;
    for(int i = s.size() - 1; i >= 0; i--){
      if(s[i] == 'C') t = t.substr(1) + t.substr(0, 1);
      if(s[i] == 'J') t = t.substr(t.size()-1) + t.substr(0, t.size()-1);
      if(s[i] == 'E'){
        if(t.size() % 2) t = t.substr(t.size() / 2 + 1) + t.substr(t.size()/2, 1) + t.substr(0, t.size()/2);
        else t = t.substr(t.size()/2) + t.substr(0, t.size()/2);
      }
      if(s[i] == 'A') reverse(t.begin(), t.end());
      if(s[i] == 'M') REP(j, t.size())if(isdigit(t[j])) t[j] = (t[j]-'0' + 1) % 10 + '0';
      if(s[i] == 'P') REP(j, t.size())if(isdigit(t[j])) t[j] = (t[j]-'0' + 9) % 10 + '0';
    }
    cout<<t<<endl;
  }
  return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
int main() {
    int n;
    cin>>n;
    for(int i=0;i<n;i++) {
        string order,mes;
        cin>>order>>mes;
        for(int i=order.size()-1;i>=0;i--) {
            if(order[i]=='C') {
                mes=mes.substr(1)+mes.substr(0,1);
            }else if(order[i]=='J') {
                mes=mes.substr(mes.size()-1,1)+mes.substr(0,mes.size()-1);
            }else if(order[i]=='E') {
                if(mes.size()%2) {
                    mes=mes.substr(mes.size()/2+1)+mes.substr(mes.size()/2,1)+mes.substr(0,mes.size()/2);
                }else {
                    mes=mes.substr(mes.size()/2)+mes.substr(0,mes.size()/2);
                }
            }else if(order[i]=='A') {
                reverse(mes.begin(),mes.end());
            }else if(order[i]=='P') {
                for(int i=0;i<mes.size();i++) {
                    if(isdigit(mes[i])) {
                        mes[i]=(mes[i]-'0'+9)%10+'0';
                    }
                }
            }else if(order[i]=='M') {
               for(int i=0;i<mes.size();i++) {
                    if(isdigit(mes[i])) {
                        mes[i]=(mes[i]-'0'+1)%10+'0';
                    }
                }
            }
        }
        cout<<mes<<endl;
    }
}

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

using namespace std;

int main()
{
  string number = "0123456789";
  int n;
  cin >> n;
  while(n--){
    string order, message;
    cin >> order >> message;
    for(int i = order.size()-1; i >= 0; i--){
      if(order[i] == 'M'){
	for(int j = 0; j < message.size(); j++){
	  if('0' <= message[j] && message[j] <= '9'){
	    int idx = number.find(message[j]);
	    message[j] = number[(idx+1)%number.size()];
	  }
	}
      } else if(order[i] == 'P'){
    	for(int j = 0; j < number.size(); j++){
	  if('0' <= message[j] && message[j] <= '9'){
	    int idx = number.find(message[j]);
	    message[j] = number[(idx-1+number.size())%number.size()];
	  }
	}	
      } else if(order[i] == 'A'){
	reverse(message.begin(), message.end());
      } else if(order[i] == 'E'){
	for(int i = 0; i < message.size() / 2; i++){
	  swap(message[i], message[i + (message.size()+1) / 2]);
	}
      } else if(order[i] == 'C'){
	message = message.substr(1, message.size()-1) + message[0];
      } else if(order[i] == 'J'){
	message = message[message.size()-1] + message.substr(0, message.size()-1);
      }
    }
    cout << message << endl;
  }
  return 0;
}

C++: #include <iostream>
#include <string>
#include <algorithm>
using namespace std;

int main(){
	int n;
	cin >> n;
	for(int t=0 ; t < n ; t++ ){
		string order, s;
		cin >> order >> s;
		reverse(order.begin(), order.end());
		for(int i=0 ; i < order.size() ; i++ ){
			char ch = order[i];
			
			if( ch == 'J' ){
				rotate( s.begin() , s.begin()+s.size()-1 , s.end() );
			}else if( ch == 'C' ){
				rotate( s.begin() , s.begin()+1 , s.end() );
			}else if( ch == 'E' ){
				string a, b, c;
				for(int k=0 ; k < s.size()/2 ; k++ ){
					a.push_back(s[k]);
				}
				if( s.size() % 2 == 1 ) b.push_back( s[s.size()/2] );
				for(int k = s.size()/2+(s.size()%2?1:0) ; k < s.size() ; k++ ){
					c.push_back(s[k]);
				}
				s = c + b + a;
			}else if( ch == 'A' ){
				reverse(s.begin(), s.end());
			}else if( ch == 'P' ){
				for(int k=0 ; k < s.size() ; k++ ){
					if( '1' <= s[k] && s[k] <= '9' ) s[k] -= 1;
					else if( s[k] == '0' ) s[k] = '9';
				}
			}else if( ch == 'M' ){
				for(int k=0 ; k < s.size() ; k++ ){
					if( '0' <= s[k] && s[k] <= '8' ) s[k] += 1;
					else if( s[k] == '9' ) s[k] = '0';
				}
			}
		}
		cout << s << endl;
	}
}