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 <algorithm>
#include <cstring>
#include <functional>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <stdlib.h>
#include <string>
#include <utility>
#include <vector>
#define rep(i, n) for (int i = 0; i < (n); i++)
#define loop(i, x, n) for (int i = (x); i < (n); i++)
#define all(v) (v).begin(), (v).end()
#define int long long
using namespace std;
const int MOD = 1e9 + 7;
const int INF = 1e8;
template<typename T> void cmax(T &a, T b) { a = max(a, b); }
template<typename T> void cmin(T &a, T b) { a = min(a, b); }

string J(string m) {
  string ret = "";
  ret += m[m.size() - 1];
  ret += m.substr(0, m.size() - 1);
  return ret;
}
string C(string m) {
  string ret = "";
  ret += m.substr(1, m.size() - 1);
  ret += m[0];
  return ret;
}
string E(string m) {
  string ret = "";
  if (m.size() % 2 == 0) {
    ret += m.substr(m.size() / 2, m.size() / 2);
    ret += m.substr(0, m.size() / 2);
  } else {
    ret += m.substr(m.size() / 2 + 1, m.size() / 2);
    ret += m[m.size() / 2];
    ret += m.substr(0, m.size() / 2);
  }
  return ret;
}
string A(string m) {
  string ret = "";
  for (int i = m.size() - 1; i >= 0; i--) ret += m[i];
  return ret;
}
string P(string m) {
  string ret = "";
  rep(i, m.size()) {
    if (isdigit(m[i])) {
      if (m[i] == '0')
        ret += '9';
      else
        ret += m[i] - 1;
    } else {
      ret += m[i];
    }
  }
  return ret;
}
string M(string m) {
  string ret = "";
  rep(i, m.size()) {
    if (isdigit(m[i])) {
      if (m[i] == '9')
        ret += '0';
      else {
        ret += m[i] + 1;
      }
    } else {
      ret += m[i];
    }
  }
  return ret;
}

signed main() {
  int n;
  cin >> n;
  rep(i, n) {
    string order, message;
    cin >> order >> message;
    for (int i = order.size() - 1; i >= 0; i--) {
      if (order[i] == 'J')
        message = J(message);
      else if (order[i] == 'C')
        message = C(message);
      else if (order[i] == 'E')
        message = E(message);
      else if (order[i] == 'A')
        message = A(message);
      else if (order[i] == 'P')
        message = P(message);
      else
        message = M(message);
    }
    cout << message << endl;
  }
  return 0;
}

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