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 <bits/stdc++.h>
using namespace std;
#define int long long   // <-----!!!!!!!!!!!!!!!!!!!

#define rep(i,n) for (int i=0;i<(n);i++)
#define rep2(i,a,b) for (int i=(a);i<(b);i++)
#define rrep(i,n) for (int i=(n)-1;i>=0;i--)
#define rrep2(i,a,b) for (int i=(b)-1;i>=(a);i--)
#define all(a) (a).begin(),(a).end()

typedef long long ll;
typedef pair<int, int> P;
typedef tuple<int, int, int> TUPLE;
typedef vector<int> V;
typedef vector<V> VV;
typedef vector<VV> VVV;

signed main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(0);

    int n;
    cin >> n;
    while (n--) {
        string s;
        cin >> s;
        string t;
        cin >> t;
        int m = t.size();

        reverse(all(s));
        rep(i, s.size()) {
            if (s[i] == 'J') {
                t = t[m - 1] + t.substr(0, m - 1);
            }
            if (s[i] == 'C') {
                t = t.substr(1) + t[0];
            }
            if (s[i] == 'E') {
                string u = "";
                u += t.substr((m + 1) / 2);
                if (m % 2 == 1) u += t[m / 2];
                u += t.substr(0, m / 2);
                t = u;
            }
            if (s[i] == 'A') {
                reverse(all(t));
            }
            if (s[i] == 'P') {
                rep(j, m) {
                    if (isdigit(t[j])) {
                        t[j] = (t[j] - '0' - 1 + 10) % 10 + '0';
                    }
                }
            }
            if (s[i] == 'M') {
                rep(j, m) {
                    if (isdigit(t[j])) {
                        t[j] = (t[j] - '0' + 1) % 10 + '0';
                    }
                }
            }
        }

        cout << t << endl;
    }
}

C++: #include <vector>
#include <list>
#include <map>
#include <set>
#include <queue>
#include <deque>
#include <stack>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
using namespace std;
#define REP(i,n) for(int i = 0; i < (int)n; i++)
#define FOR(i,a,b) for(int i = a; i < (int)b; i++)
#define pb push_back
#define mp make_pair
typedef vector<int> vi;
typedef pair<int, int> pi;
typedef long long ll;
const int INF = 1<<28;
const ll MOD = 1000000007;
const int dx[] = {1, 0, -1, 0}, dy[] = {0, 1, 0, -1};

void j(string &s) {
	s = s[s.size()-1] + s;
	s.erase(s.end()-1);
}
void c(string &s) {
	s = s + s[0];
	s.erase(s.begin());
}
void e(string &s) {
	if(s.size()%2)
		REP(i, s.size()/2)
			swap(s[i], s[s.size()/2+i+1]);
	else
		REP(i, s.size()/2)
			swap(s[i], s[s.size()/2+i]);
}
void a(string &s) {
	reverse(s.begin(), s.end());
}
void p(string &s) {
	REP(i, s.size())
		if(isdigit(s[i]))
			s[i] = s[i] == '0' ? '9' : s[i]-1;
}
void m(string &s) {
	REP(i, s.size())
		if(isdigit(s[i]))
			s[i] = s[i] == '9' ? '0' : s[i]+1;

}

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);

	int n; cin >> n;
	REP(_, n) {
		string x, y;
		cin >> x >> y;

		reverse(x.begin(), x.end());
		REP(i, x.size()) {
			if(x[i] == 'J') j(y);
			if(x[i] == 'C') c(y);
			if(x[i] == 'E') e(y);
			if(x[i] == 'A') a(y);
			if(x[i] == 'P') p(y);
			if(x[i] == 'M') m(y);
		}
		cout << y << endl;
	}
	return 0;
}

C++: // http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=1240

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

int main() {
  int N;
  cin >> N;
  for (int i=0; i<N; i++) {
    string S, O;
    cin >> O >> S;
    reverse(O.begin(), O.end());
    for (auto i=0; i<O.size(); i++) {
      switch(O[i]) {
      case 'J':
	S = S[S.size()-1] + S.substr(0, S.size()-1);
	break;
      case 'C':
	S = S.substr(1) + S[0];
	break;
      case 'E':
	if (S.size()%2 == 0) {
	  S = S.substr(S.size()/2) + S.substr(0, S.size()/2);
	} else {
	  S = S.substr(S.size()/2+1) + S[S.size()/2] 
	    + S.substr(0, S.size()/2);
	}
	break;
      case 'A':
	reverse(S.begin(), S.end());
	break;
      case 'P':
	for (auto i=0; i<S.size(); i++) {
	  if (isdigit(S[i])) {
	    S[i] = (char)((((int)S[i] - '0')+10 -1)%10 + '0');  
	  }
	}
	break;
      case 'M':
	for (auto i=0; i<S.size(); i++) {
	  if (isdigit(S[i])) {
	    S[i] = (char)((((int)S[i] - '0')+10 +1)%10 + '0');  
	  }
	}
	break;
      default:
	break;
      }
    }
    cout << S << endl;
  }
}