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 <vector>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <queue>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <complex>
#include <cmath>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <ctime>
#include <fstream>
#include <stdio.h>

using namespace std;

//conversion
//------------------------------------------
inline int toInt(string s) {int v; istringstream sin(s);sin>>v;return v;}
template<class T> inline string toString(T x) {ostringstream sout;sout<<x;return sout.str();}

//typedef
//------------------------------------------
typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<double> VEC;
typedef vector<VEC> MAT;
typedef vector<string> VS;
typedef pair<int, int> PII;
typedef pair<int, PII> TIII;
typedef long long LL;
typedef vector<LL> VLL;
typedef vector<VLL> VVLL;
//container util

//------------------------------------------
#define ALL(a)  (a).begin(),(a).end()
#define RALL(a) (a).rbegin(), (a).rend()
#define PB push_back
#define MP make_pair
#define SZ(a) int((a).size())
#define EACH(i,c) for(typeof((c).begin()) i=(c).begin(); i!=(c).end(); ++i)
#define EXIST(s,e) ((s).find(e)!=(s).end())
#define SORT(c) sort((c).begin(),(c).end())
#define MT(a,b,c) MP(a, MP(b, c))
#define T1 first
#define T2 second.first
#define T3 second.second

//repetition
//------------------------------------------
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n)  FOR(i,0,n)
#define EPS 1.0e-9

string conv(string s, char c){
	int n=s.length();
	if(c=='J'){
		s=s[n-1]+s.substr(0,n-1);
	}else if(c=='C'){
		s=s.substr(1,n-1)+s[0];
	}else if(c=='E'){
		if(n%2)s=s.substr((n+1)/2,n/2)+s[(n-1)/2]+s.substr(0,n/2);
		else s=s.substr(n/2,n/2)+s.substr(0,n/2);
	}else if(c=='A'){
		reverse(ALL(s));
	}else if(c=='P'){
		REP(i,n)if(isdigit(s[i]))s[i]=((s[i]-'0'+9)%10)+'0';
	}else if(c=='M'){
		REP(i,n)if(isdigit(s[i]))s[i]=((s[i]-'0'+1)%10)+'0';
	}
	return s;	
}

int main(){
	int t;
	cin >> t;
	REP(i,t){
		string s, t;
		cin>>s>>t;
		REP(i,s.size())t=conv(t, s[s.size()-i-1]);
		cout << t << endl;
	}
	return 0;
}

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

string oom, mes;


void rJ() {
  const string tmp = mes;
  mes = tmp[tmp.length()-1] + tmp.substr(0, tmp.length()-1);
}
void rC() {
  const string tmp = mes;
  mes = tmp.substr(1) + tmp[0];
}
void rE() {
  string l = mes.substr(0, mes.length()/2);
  string r = mes.substr((mes.length()+1)/2);
  if(mes.length() % 2 != 0) {
    mes = r + mes[mes.length()/2] + l;
  } else {
    mes = r + l;
  }
}
void rA() {
  reverse(mes.begin(), mes.end());
}

void rP() {
  for(int i = 0; i < mes.length(); ++i) {
    if(isdigit(mes[i])) {
      mes[i] = (mes[i]-'0'+9)%10+'0';
    }
  }
}
void rM() {
  for(int i = 0; i < mes.length(); ++i) {
    if(isdigit(mes[i])) {
      mes[i] = (mes[i]-'0'+1)%10+'0';
    }
  }
}

void solve() {
  reverse(oom.begin(), oom.end());
  for(int i = 0; i < oom.length(); ++i) {
    switch(oom[i]) {
    case 'J': rJ(); break;
    case 'C': rC(); break;
    case 'E': rE(); break;
    case 'A': rA(); break;
    case 'P': rP(); break;
    case 'M': rM(); break;
    }
  }
  cout << mes << endl;
}

main() {
  int n;
  cin >> n;
  for(int i = 0; i < n; ++i) {
    cin >> oom;
    cin >> mes;
    solve();
  }
}

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

int main()
{
    int n, len;
    cin >> n;
    string msg, srv;
    while (cin >> srv >> msg, n--) {
        len = msg.size();
        for (int i = srv.size() - 1; i >= 0; --i) {
            if (srv[i] == 'J') {
                rotate(msg.begin(), msg.end() - 1, msg.end());
            } else if (srv[i] == 'C') {
                rotate(msg.begin(), msg.begin() + 1, msg.end());
            } else if (srv[i] == 'E') {
                if (len % 2)
                    msg = msg.substr(len / 2 + 1) + msg[len / 2] + msg.substr(0, len / 2);
                else
                    msg = msg.substr(len / 2) + msg.substr(0, len / 2);
            } else if (srv[i] == 'A') {
                reverse(msg.begin(), msg.end());
            } else if (srv[i] == 'P') {
                for (int j = 0; j < len; ++j) {
                    if (msg[j] >= '0' && msg[j] <= '9')
                        msg[j] = (msg[j] + '9') % ':';
                }
            } else {
                for (int j = 0; j < len; ++j) {
                    if (msg[j] >= '0' && msg[j] <= '9')
                        msg[j] = (msg[j] + 1) % '9';
                }
            }
        }
        cout << msg << endl;
    }
    return 0;
}