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 <cstdio>
#include <cstdlib>
#include <queue>
#include <stack>
#include <vector>
#include <algorithm>
#include <string>
#include <cstring>
#include <cmath>
#include <complex>
#include <map>
#include <climits>
#include <sstream>
using namespace std;
 
#define reep(i,a,b) for(int i=(a);i<(b);++i)
#define rep(i,n) reep((i),0,(n))
#define ALL(v) (v).begin(),(v).end()
#define PB push_back
#define EPS 1e-8
#define F first
#define S second
#define mkp make_pair
 
static const double PI=6*asin(0.5);
typedef long long ll;
typedef complex<double> CP;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef vector<int> vint;
static const int INF=1<<24;
 
template <class T>
void initvv(vector<vector<T> > &v,int a,int b, const T  &t = T()){
    v.assign(a,vector<T>(b,t));
}
 
//v.erase(unique(v.begin(),v.end()),v.end());
 
 
string mes_a(string in){
	string res=string(in.rbegin(),in.rend());
	return res;
}
string mes_j(string in){
	return in.substr(in.size()-1)+in.substr(0,in.size()-1);
}
string mes_c(string in){
	return in.substr(1)+in.substr(0,1);
}
string mes_e(string in){
	int t=in.size()/2;
	rep(i,t){
		swap(in[i],in[i+in.size()-t]);
	}
	return in;
}
string mes_p(string in){
	stringstream ss;
	ss<<in;
	stringstream res;
	rep(i,in.size()){
		char t;
		ss>>t;
		if('0'<=t&&t<='9'){
			t=((t-'0')+9)%10+'0';
		}
		res<<t;
	}
	string ret;
	res>>ret;
	return ret;
}
string mes_m(string in){
	stringstream ss;
	ss<<in;
	stringstream res;
	rep(i,in.size()){
		char t;
		ss>>t;
		if('0'<=t&&t<='9'){
			t=((t-'0')+1)%10+'0';
		}
		res<<t;
	}
	string ret;
	res>>ret;
	return ret;
}


int main(){
	int n;
	cin>>n;
	rep(i,n){
		string s1,s2;	
		cin>>s1>>s2;
		rep(j,s1.size()){
			int i=s1.size()-1-j;
			// cout<<s2<<endl;
			if(s1[i]=='J'){
				s2=mes_j(s2);
			}
			else if(s1[i]=='C'){
				s2=mes_c(s2);
			}
			else if(s1[i]=='E'){
				s2=mes_e(s2);
			}
			else if(s1[i]=='A'){
				s2=mes_a(s2);
			}
			else if(s1[i]=='P'){
				s2=mes_p(s2);
			}
			else if(s1[i]=='M'){
				s2=mes_m(s2);
			}
		}
		cout<<s2<<endl;
	}
}

C++: #include<bits/stdc++.h>
using namespace std;
int main(){
  int n;
  cin>>n;
  while(n--){
    string q,s;
    cin>>q>>s;
    for(int i=0;i<q.size();i++){
      if(q[i]=='C')s=s.substr(1,s.size()-1)+s[0];
      if(q[i]=='J')s=s[s.size()-1]+s.substr(0,s.size()-1);
      if(q[i]=='E')
	for(int j=0;j<s.size()/2;j++)swap(s[j],s[(s.size()+1)/2+j]);
      if(q[i]=='A')reverse(s.begin(),s.end());
      if(q[i]=='M')
	for(int j=0;j<s.size();j++)
	  if(isdigit(s[j]))s[j]=((s[j]-'0')+1)%10+'0';
      if(q[i]=='P')
	for(int j=0;j<s.size();j++)
	  if(isdigit(s[j]))s[j]=((s[j]-'0'+10)-1)%10+'0';
    }
    cout<<s<<endl;
  }
  return 0;
}

C++: #include <cstdio>
#include <algorithm>
using std::swap;

void J(char s[], int len){
    char tmp = s[len-1];
    for(int i=len-1;i>0;i--){
        s[i] = s[i-1];
    }s[0] = tmp;
}
void C(char s[], int len){
    char tmp = s[0];
    for(int i=0;i<len-1;i++){
        s[i] = s[i+1];
    }s[len-1] = tmp;
}
void E(char s[], int len){
    int mid = len/2;
    for(int i=0;i<mid;i++){
        swap(s[i], s[len-mid+i]);
    }
}
void A(char s[], int len){
    char tmp = s[len-1];
    for(int i=0;i<len-1-i;i++){
        swap(s[i], s[len-1-i]);
    }
}
void P(char s[], int len){
    for(int i=0;i<len;i++){
        if('0'<=s[i] && s[i]<='9'){
            s[i] = '0'+(s[i]-'0'+9)%10;
        }
    }
}
void M(char s[], int len){
    for(int i=0;i<len;i++){
        if('0'<=s[i] && s[i]<='9'){
            s[i] = '0'+(s[i]-'0'+1)%10;
        }
    }
}

int main(){
    int N;
    scanf("%d", &N);
    while(N--){
        char s1[50], s2[50];
        scanf("%s %s", s1, s2);
        int len1;
        for(len1=0 ; s1[len1]!='\0' ; len1++);
        int len2;
        for(len2=0 ; s2[len2]!='\0' ; len2++);
        
        for(int i=len1-1;i>=0;i--){
            if(s1[i] == 'J') J(s2, len2);
            if(s1[i] == 'C') C(s2, len2);
            if(s1[i] == 'E') E(s2, len2);
            if(s1[i] == 'A') A(s2, len2);
            if(s1[i] == 'P') P(s2, len2);
            if(s1[i] == 'M') M(s2, len2);
        }
        printf("%s\n", s2);
    }
    return 0;
}

C++: //37
#include<iostream>
#include<string>
#include<algorithm>
#include<cctype>

using namespace std;

int main(){
  int n;
  cin>>n;
  while(n--){
    string r,m;
    cin>>r>>m;
    for(int i=r.size()-1;i>=0;i--){
      switch(r[i]){
      case 'J':
	if(m.size()>1){
	  rotate(m.begin(),m.end()-1,m.end());
	}
	break;
      case 'C':
	if(m.size()>1){
	  rotate(m.begin(),m.begin()+1,m.end());
	}
	break;
      case 'E':
	{
	  string n;
	  n=m.substr((m.size()+1)/2);
	  if(m.size()%2){
	    n+=m[m.size()/2];
	  }
	  n+=m.substr(0,m.size()/2);
	  m=n;
	}
	break;
      case 'A':
	reverse(m.begin(),m.end());
	break;
      case 'P':
      case 'M':
	for(int j=0;j<m.size();j++){
	  if(isdigit(m[j])){
	    m[j]=(m[j]-'0'+(r[i]=='M')-(r[i]=='P')+10)%10+'0';
	  }
	}
	break;
      }
    }
    cout<<m<<endl;
  }
  return 0;
}