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 <vector>
#include <string>
#include <map>
#include <algorithm>

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

using namespace std;

int main() {
  int n;
  cin>>n;
  REP(i,n){
    string cmd;
    cin>>cmd;
    string str;
    cin>>str;
    reverse(begin(cmd),end(cmd));
    for(char c:cmd){
      switch(c){
        case 'C': {
          string body=str.substr(1);
          string head=str.substr(0,1);
          str = body + head;
          break;
        }
        case 'J': {
          string body=str.substr(0,str.size()-1);
          string head=str.substr(str.size()-1);
          str = head + body;
          break;
        }
        case 'E': {
          int mid=str.size()/2;
          string fwd=str.substr(0,mid);
          string bwd=str.substr(str.size()-mid);
          if((str.size()%2)==1){
            str=bwd+str[mid]+fwd;
          }else{
            str=bwd+fwd;
          }
          break;
        }
        case 'A': {
          reverse(begin(str),end(str));
          break;
        }
        case 'M': {
          for(char& d:str){
            if('0' <= d && d < '9')
              ++d;
            else if(d == '9')
              d = '0';
          }
          break;
        }
        case 'P': {
          for(char& c:str){
            if('0' < c && c <= '9')
              --c;
            else if(c == '0')
              c = '9';
          }
          break;
        }
      }
    }
    cout<<str<<endl;
  }
  return 0;
}

C++: #include <cstdio>
#include <utility>
#include <cmath>
#include <algorithm>
#include <iostream>
#include <iomanip>
#include <vector>
#include <string>
#define REP(i,n) for(int i=0;i<n;i++)
typedef long long ll;
using namespace std;
typedef vector<ll> vl;
typedef pair<ll,ll> pll;
typedef vector<pll> vpll;
typedef vector<string> vs;

int main() 
{
	int n;
	cin >> n;
	cin.ignore();
	REP(i,n){
		
		string s,c;
		getline(cin,s);
		getline(cin,c);
		
		char a[10]={'0','1','2','3','4','5','6','7','8','9'};
		
		REP(j,s.length()){
			switch(s[s.length()-1-j]){
				case 'C':
				rotate(c.begin(),c.begin()+1,c.begin()+c.length());
				break;
				case 'J':
				rotate(c.begin(),c.begin()+c.length()-1,c.begin()+c.length());
				break;
			  case 'E':{
				string tmp1="";string tmp2="";string tmp3="";
				REP(k,c.length()/2){tmp1+=c[k];}
				REP(k,c.length()/2){tmp3+=c[c.length()-c.length()/2+k];}
				if(c.length()%2==1){tmp2+=c[c.length()/2];}
				c = tmp3+tmp2+tmp1;}
				break;
				case 'A':
				reverse(c.begin(),c.end());
				break;
				case 'M':
				REP(k,c.length()){REP(l,10){if(a[l]==c[k]){c[k]=a[(l+1+10)%10];break;}}}
				break;
				case 'P':
				REP(k,c.length()){REP(l,10){if(a[l]==c[k]){c[k]=a[(l-1+10)%10];break;}}}
				break;
			}
		}
		cout << c << endl;
	}	
		return 0;
}

C++: #include <stdio.h>
#include <stdlib.h>
#include <iostream>
#include <vector>
#include <string>
#include <queue>
#include <algorithm>
#include <math.h>
#include <utility>
#include <set>
#include <map>
#include <cstring>
#include <cstdio>
#include <stack>
#define INF 1000000000
#define rep(i,n) for(int i =0;i<n;i++)
using namespace std;
typedef long long int ll;

string A(string s){
    reverse(s.begin(),s.end());
    return s;
}

string J(string s){
    string ss = s.substr(s.length()-1,1),sss=s.substr(0,s.length()-1);
    return ss+sss;
}

string C(string s){
    string ss = s.substr(0,1),sss=s.substr(1,s.length()-1);
    return sss+ss;
}

string E(string s){
    if(s.length()%2==0){
        string ss = s.substr(0,s.length()/2);
        string sss = s.substr(s.length()/2,s.length()/2);
        return sss+ss;
    }else{
        string ss = s.substr(0,s.length()/2);
        string tt = s.substr(s.length()/2,1);
        string sss = s.substr(s.length()/2+1,s.length()/2);
        return sss+tt+ss;
    }
}

string P(string s){
    for (int i=0; i<s.length(); i++) {
        if (s[i]=='9' or s[i]=='1' or s[i]=='2' or s[i]=='3' or s[i]=='4' or s[i]=='5' or s[i]=='6' or s[i]=='7' or s[i]=='8') {
            s[i]=(char)((int)s[i]-1);
            continue;
        }
        if (s[i]=='0') {
            s[i]='9';
        }
    }
    return s;
}

string M(string s){
    for (int i=0; i<s.length(); i++) {
        if (s[i]=='0' or s[i]=='1' or s[i]=='2' or s[i]=='3' or s[i]=='4' or s[i]=='5' or s[i]=='6' or s[i]=='7' or s[i]=='8') {
            s[i]=(char)((int)s[i]+1);
            continue;
        }
        if (s[i]=='9') {
            s[i]='0';
        }
    }
    return s;
}


int main(){
    int n;
    cin >> n;
    for (int wq=0; wq<n; wq++) {
        string t,s;
        cin >> t >>s;
        for (int i= t.length()-1; i>=0; i--) {
            if(t[i]=='J') s = J(s);
            if(t[i]=='C') s = C(s);
            if(t[i]=='E') s = E(s);
            if(t[i]=='A') s = A(s);
            if(t[i]=='P') s = P(s);
            if(t[i]=='M') s = M(s);
        }
        cout << s <<endl;
    }
}