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<cctype>
using namespace std;

void relay(char op, string &s){

}

int main(){
    int n;
    cin >> n;

    while(n-- > 0){
        string op, s;
        cin >> op >> s;

        reverse(op.begin(), op.end());
        int len = s.length();
        
        for(char x : op){
            if(x == 'J'){
                s = s.substr(len-1, 1) + s.substr(0, len-1);
            }else if(x == 'C'){
                s = s.substr(1) + s.substr(0,1);
            }else if(x == 'E'){
                if(len % 2 == 1){
                    s = s.substr(len/2+1) + s[len/2] + s.substr(0, len/2);
                }else{
                    s = s.substr(len/2) + s.substr(0, len/2);
                }
            }else if(x == 'A'){
                reverse(s.begin(), s.end());
            }else if(x == 'P'){
                for(int i = 0; i < len; i++){
                    if(isdigit(s[i]))   s[i] = '0' + (s[i]-'0'-1+10)%10;
                }
            }else if(x == 'M'){
                for(int i = 0; i < len; i++){
                    if(isdigit(s[i]))   s[i] = '0' + (s[i]-'0'+1)%10;
                }
            }
        }

        cout << s << endl;
    }
    return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;

#define REP(i,n) for(int i=0;i<(n);i++)
#define ALL(v) (v).begin(),(v).end()
#define int long long
typedef pair<int,int> P;

//-----------------------------------------------------------------------

void decode(string &s,char c)
{
    int l=s.size();
    if(c=='J'){
	if(l>0) s=s[l-1]+s.substr(0,l-1);
    }
    else if(c=='C'){
	if(l>0) s=s.substr(1)+s[0];
    }
    else if(c=='E'){
	if(l%2==0) s=s.substr(l/2)+s.substr(0,l/2);
	else s=s.substr(l/2+1)+s[l/2]+s.substr(0,l/2);
    }
    else if(c=='A'){
	reverse(ALL(s));
    }
    else if(c=='P'){
	REP(i,s.size()){
	    if(isdigit(s[i])) s[i]=(s[i]-'0'+9)%10+'0';
	}
    }
    else{
	REP(i,s.size()){
	    if(isdigit(s[i])) s[i]=(s[i]-'0'+1)%10+'0';
	}
    }
}
    
signed main()
{
    cin.tie(0);
    ios::sync_with_stdio(false);

    int n; cin>>n;
    REP(i,n){
	string s,msg;
	cin>>s>>msg;
	for(int i=s.size()-1;i>=0;i--){
	    decode(msg,s[i]);
	}
	cout<<msg<<endl;
    }

}

C++: #include<iostream>
#include<string>
#include<algorithm>
#include<cstring>
#include<cctype>

using namespace std;

string revJ(string t){
ÃÂ ÃÂ string ret = t;
ÃÂ ÃÂ ret.insert(ret.begin(),t[t.length()-1]);
ÃÂ ÃÂ ret.erase(ret.end()-1);
ÃÂ ÃÂ return ret;
}
string revC(string t){
ÃÂ ÃÂ string ret = t;
ÃÂ ÃÂ ret += t[0];
ÃÂ ÃÂ ret.erase(ret.begin());
ÃÂ ÃÂ return ret;
}
string revE(string t){
ÃÂ ÃÂ char c=0;
ÃÂ ÃÂ if(t.length()==1)return t;
ÃÂ ÃÂ if(t.length()%2){
ÃÂ ÃÂ  ÃÂ c = t[t.length()/2];
ÃÂ ÃÂ  ÃÂ t.erase(t.begin()+t.length()/2);
ÃÂ ÃÂ }
ÃÂ ÃÂ string l = t.substr(0,t.length()/2);
ÃÂ ÃÂ string r = t.substr(t.length()/2,t.length()-t.length()/2);
ÃÂ ÃÂ if(c){
ÃÂ ÃÂ  ÃÂ return r+c+l;
ÃÂ ÃÂ }else return r+l;
}
string revA(string t){
ÃÂ ÃÂ string ret = t;
ÃÂ ÃÂ reverse(ret.begin(),ret.end());
ÃÂ ÃÂ return ret;
}
string revP(string t){
ÃÂ ÃÂ //dec
ÃÂ ÃÂ string ret = t;
ÃÂ ÃÂ for(int i = 0; i < (signed)ret.length(); ++i){
ÃÂ ÃÂ  ÃÂ if( isdigit(ret[i]) ){
ÃÂ ÃÂ  ÃÂ  ÃÂ ret[i]--;
ÃÂ ÃÂ  ÃÂ  ÃÂ if(ret[i]<'0')ret[i]='9';
ÃÂ ÃÂ  ÃÂ }
ÃÂ ÃÂ }
ÃÂ ÃÂ return ret;
}
string revM(string t){
ÃÂ ÃÂ //inc
ÃÂ ÃÂ string ret = t;
ÃÂ ÃÂ for(int i = 0; i < (signed)ret.length(); ++i){
ÃÂ ÃÂ  ÃÂ if( isdigit(ret[i]) ){
ÃÂ ÃÂ  ÃÂ  ÃÂ ret[i]++;
ÃÂ ÃÂ  ÃÂ  ÃÂ if(ret[i]>'9')ret[i]='0';
ÃÂ ÃÂ  ÃÂ }
ÃÂ ÃÂ }
ÃÂ ÃÂ return ret;
}

int main()
{
ÃÂ ÃÂ int n;
ÃÂ ÃÂ cin >> n;
ÃÂ ÃÂ for(int i = 0; i < n; ++i){
ÃÂ ÃÂ  ÃÂ string order;
ÃÂ ÃÂ  ÃÂ string msg;
ÃÂ ÃÂ  ÃÂ cin >> order >> msg;
ÃÂ ÃÂ  ÃÂ for(int i = (int)order.length()-1; i>=0; --i){
ÃÂ ÃÂ  ÃÂ  ÃÂ if( order[i] == 'J' ){
	msg = revJ( msg );
ÃÂ ÃÂ  ÃÂ  ÃÂ }
ÃÂ ÃÂ  ÃÂ  ÃÂ if( order[i] == 'C' ){
	msg = revC( msg );
ÃÂ ÃÂ  ÃÂ  ÃÂ }
ÃÂ ÃÂ  ÃÂ  ÃÂ if( order[i] == 'E' ){
	msg = revE( msg );
ÃÂ ÃÂ  ÃÂ  ÃÂ }
ÃÂ ÃÂ  ÃÂ  ÃÂ if( order[i] == 'A' ){
	msg = revA( msg );
ÃÂ ÃÂ  ÃÂ  ÃÂ }
ÃÂ ÃÂ  ÃÂ  ÃÂ if( order[i] == 'P' ){
	msg = revP( msg );
ÃÂ ÃÂ  ÃÂ  ÃÂ }
ÃÂ ÃÂ  ÃÂ  ÃÂ if( order[i] == 'M' ){
	msg = revM( msg );
ÃÂ ÃÂ  ÃÂ  ÃÂ }
ÃÂ ÃÂ  ÃÂ }
ÃÂ ÃÂ  ÃÂ cout << msg << endl;
ÃÂ ÃÂ }
ÃÂ ÃÂ return 0;
}