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 <string>
#include <vector>
#include <algorithm>
#include <cmath>
#include <cstdio>
#include <functional>
#include <numeric>
#include <stack>
#include <queue>
#include <map>
#include <set>
#include <utility>
#include <sstream>
#include <complex>
#include <fstream>

using namespace std;

#define FOR(i,a,b) for(long long i=(a);i<(b);i++)
#define REP(i,N) for(long long i=0;i<(N);i++)
#define ALL(s) (s).begin(),(s).end()
#define fi first
#define se second

#define PI acos(-1.0)
#define INF 10e9+9
#define EPS 1e-10
#define MAX_N 100100
#define MAX_M 100100

typedef long long ll;
typedef pair<ll, ll> P;
typedef pair<double, double> PD;
typedef pair<string, ll> PS;
typedef vector<ll> V;
typedef pair<P, char> PC;

int n;
string s, ans;

int main(){
	cin >> n;
	REP(k, n){
		cin >> s >> ans;
		reverse(ALL(s));
		REP(i,s.size()){
			if (s[i] == 'J'){
				ans = ans[ans.size() - 1] + ans.substr(0, ans.size() - 1);
			}
			else if (s[i] == 'C'){
				ans = ans.substr(1, ans.size() - 1) + ans[0];
			}
			else if (s[i] == 'E'){
				int num = ans.size() / 2;
				if (ans.size() % 2 == 1){
					ans = ans.substr(num + 1) + ans[num] + ans.substr(0, num);
				}
				else{
					ans = ans.substr(num) + ans.substr(0, num);
				}
			}
			else if (s[i] == 'A'){
				reverse(ALL(ans));
			}
			else if (s[i] == 'P'){
				REP(j, ans.size()){
					if (ans[j] >= '1'&&ans[j] <= '9'){
						ans[j] = (char)(ans[j] - 1);
					}
					else if (ans[j] == '0'){
						ans[j] = '9';
					}
				}
			}
			else{
				REP(j, ans.size()){
					if (ans[j] >= '0'&&ans[j] <= '8'){
						ans[j] = (char)(ans[j] + 1);
					}
					else if (ans[j] == '9'){
						ans[j] = '0';
					}
				}
			}
		}
		cout << ans << endl;
	}
}

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

void dec(string& a)
{
	for(int i=0; i<a.size(); i++) {
		if(isdigit(a[i])) {
			a[i] = (a[i] - '0' + 9) % 10 + '0';
		}
	}
}

void inc(string& a)
{
	for(int i=0; i<a.size(); i++) {
		if(isdigit(a[i])) {
			a[i] = (a[i] - '0' + 1) % 10 + '0';
		}
	}
}

void half(string& a)
{
	int N = a.size();
	for(int i=0; i<N/2; i++) swap(a[i], a[N/2+i+N%2]);
}

int main()
{
	int N;
	cin >> N;
	while(N--) {
		string cmd, str;
		cin >> cmd;
		reverse(cmd.begin(), cmd.end());

		cin >> str;
		for(int i=0; i<cmd.size(); i++) {
			if(cmd[i] == 'A') reverse(str.begin(), str.end());
			if(cmd[i] == 'M') inc(str);
			if(cmd[i] == 'P') dec(str);
			if(cmd[i] == 'C') rotate(str.begin(), str.begin() + 1, str.end());
			if(cmd[i] == 'J') rotate(str.begin(), str.end() - 1, str.end());
			if(cmd[i] == 'E') half(str);
		}

		cout << str << endl;
	}


}

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

int main() {
  int n; cin >> n;
  while(n--) {
    string member; cin >> member;
    string s; cin >> s;
    int siz = s.size();
    for(int i = member.size()-1; i >= 0; i--) {
      char c = member[i];
      if(c == 'C') {;
        s = s.substr(1, siz) + s[0];
      } else if(c == 'J') {
        s = s[siz-1] + s.substr(0, siz-1);
      } else if(c == 'E') {
        string temp = s.substr(0, siz/2);
        s = s.substr(siz/2, siz) + temp;
      } else if(c == 'A') {
        reverse(s.begin(), s.end());
      } else if(c == 'M') {
        for(int j = 0; j < siz; j++) {
          if('0' <= s[j] && s[j] <= '9') {
            if(s[j] != '9') s[j]++;
            else s[j] = '0';
          }
        }
      } else if(c == 'P') {
        for(int j = 0; j < siz; j++) {
          if('0' <= s[j] && s[j] <= '9') {
            if(s[j] != '0') s[j]--;
            else s[j] = '9';
          }
        }
      }
    }
    cout << s << endl;
  }
}