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<algorithm>
#include<string>
#include<vector>
#include<stack>
using namespace std;

vector<char> v;

void C(){
	v.push_back(v[0]);
	v.erase(v.begin());
}

void J(){
	v.insert(v.begin(),v[v.size()-1]);
	v.pop_back();
}

void E(){
	stack<char> st[2];
	for(int i=0;i<v.size()/2;i++){
		st[0].push(v[i]);
		st[1].push(v[v.size()-1-i]);
	}
	for(int i=0;i<v.size()/2;i++){
		v[i]=st[1].top();
		v[v.size()-1-i]=st[0].top();
		st[0].pop(),st[1].pop();
	}
}

void A(){
	stack<char> st;
	for(int i=0;i<v.size();i++)st.push(v[i]);
	for(int i=0;i<v.size();i++){
		v[i]=st.top();
		st.pop();
	}
}

void M(){
	for(int i=0;i<v.size();i++){
		if(v[i]>='0'&&v[i]<='9'){
			v[i]=((v[i]-'0')+1)%10+'0';
		}
	}
}

void P(){
	for(int i=0;i<v.size();i++){
		if(v[i]>='0'&&v[i]<='9'){
			v[i]=((v[i]-'0')+9)%10+'0';
		}
	}
}

int main(){
	int n;
	string s,q;
	cin>>n;
	while(n--){
		cin>>s>>q;
		v.clear();
		for(int i=0;i<q.size();i++)v.push_back(q[i]);
		for(int i=s.size()-1;i>=0;i--){
			if(s[i]=='J')J();
			if(s[i]=='C')C();
			if(s[i]=='E')E();
			if(s[i]=='A')A();
			if(s[i]=='P')P();
			if(s[i]=='M')M();
		}
		for(int i=0;i<v.size();i++)cout<<v[i];
		cout<<endl;
	}
	return 0;
}

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

string J(string str){
    char tmp = str[str.size() - 1];
    for(int i = str.size() - 1; i > 0; i--) str[i] = str[i - 1];
    str[0] = tmp;
    return str;
}

string C(string str){
    char tmp = str[0];
    for(int i = 0; i < str.size() - 1; i++) str[i] = str[i + 1];
    str[str.size() - 1] = tmp;
    return str;
}
string E(string str){
    string s1, s2;
    int strSize = str.size() / 2;
    if(str.size() % 2 != 0) strSize++;
    s2 = str.substr(strSize);
    s1 = str.substr(0, s2.size());
    if(str.size() % 2 == 0) return s2 + s1;
    else return s2 + str[str.size() / 2] + s1;
}

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

string P(string str){
    stringstream ss;
    for(int i = 0; i < str.size(); i++){
        if(isalpha(str[i])){
            ss <<str[i];
        } else{
            int tmp = str[i] - '0';
            tmp--;
            if(tmp == -1) tmp = 9;
            ss <<tmp;
        }
    }
    return ss.str();
}

string M(string str){
    stringstream ss;
    for(int i = 0; i < str.size(); i++){
        if(isalpha(str[i])){
            ss <<str[i];
        } else{
            int tmp = str[i] - '0';
            tmp++;
            if(tmp == 10) tmp = 0;
            ss <<tmp;
        }
    }
    return ss.str();

}
int main(){
    int n;
    cin >>n;
    for(int i = 0; i < n; i++){
        string str, ser;
        cin >>ser >>str;
        reverse(ser.begin(), ser.end());
        for(int i = 0; i < ser.size(); i++){
            switch(ser[i]){
                case 'J':
                    str = J(str); break;
                case 'C':
                    str = C(str); break;
                case 'E':
                    str = E(str); break;
                case 'A':
                    str = A(str); break;
                case 'P':
                    str = P(str); break;
                case 'M':
                    str = M(str);
            }
        }
        cout <<str <<endl;
    }
    return 0;
}