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 <algorithm>

using namespace std;

bool check(char c)
{
	char v = '0';
	for(int i = 0; i <= 9; i++){
		if(c == (char)(v+i)){
			return true;
		}
	}
	
	return false;
}

string cfunc(string str, int n)
{
	string s = str.substr(1);
	s += str[0];
	
	return s;
}

string jfunc(string str, int n)
{
	string s = str.substr(0, n-1);
	s = str[n-1] + s;
	
	return s;
}

string efunc(string str, int n)
{
	string s;
	if(n%2 == 0){
		s = str.substr(n/2);
		s += str.substr(0, n/2);
	} else {
		s = "";
		for(int i = n/2+1; i < n; i++){
			s += str[i];
		}
		s += str[n/2];
		for(int i = 0; i < n/2; i++){
			s += str[i];
		}
	}
	
	return s;
}

string afunc(string str, int n)
{
	string s = str;
	reverse(s.begin(), s.end());
	
	return s;
}

string pfunc(string str, int n)
{
	string s = str;
	
	for(int i = 0; i < n; i++){
		if(check(s[i])){
			if(s[i] == '0'){
				s[i] = '9';
			} else {
				s[i] = (char)(s[i]-1);
			}
		}
	}
	
	return s;
}

string mfunc(string str, int n)
{
	string s = str;
	
	for(int i = 0; i < n; i++){
		if(check(s[i])){
			if(s[i] == '9'){
				s[i] = '0';
			} else {
				s[i] = (char)(s[i]+1);
			}
		}
	}
	
	return s;
}

int main()
{
	int n, l, m;
	string str, st;
	cin >> n;
	
	while(n--){
		cin >> st;
		cin >> str;
		l = st.size();
		m = str.size();
		
		for(int i = l-1; i >= 0; i--){
			if(st[i] == 'J'){
				str = jfunc(str, m);
			} else if(st[i] == 'C'){
				str = cfunc(str, m);
			} else if(st[i] == 'E'){
				str = efunc(str, m);
			} else if(st[i] == 'A'){
				str = afunc(str, m);
			} else if(st[i] == 'P'){
				str = pfunc(str, m);
			} else if(st[i] == 'M'){
				str = mfunc(str, m);
			}
		}
		
		cout << str << endl;
	}
	
	return 0;
}

C++: #include<iostream>
#include<string>
#include<algorithm>
#include<map>
#include<set>
#include<utility>
#include<vector>
#include<cmath>
#include<cstdio>
#define loop(i,a,b) for(int i=a;i<b;i++) 
#define rep(i,a) loop(i,0,a)
#define pb push_back
#define mp make_pair
#define it ::iterator
#define all(in) in.begin(),in.end()
const double PI=acos(-1);
const double ESP=1e-10;
using namespace std;
int main(){
  int n;
  cin>>n;
  while(n--){
    string in,s;
    cin>>in>>s;
    for(int i=in.size()-1;i>=0;i--){
      if(in[i]=='C')
	s=s.substr(1)+s[0];
      else if(in[i]=='A')
	reverse(all(s));
      else if(in[i]=='E'){
	//cout<<s.size()<<endl;
	int tmp=s.size();
	if(!(tmp%2))
	  s=s.substr(tmp/2)+s.substr(0,tmp/2);
	else
	  s=s.substr(tmp/2+1)+s[tmp/2]+s.substr(0,tmp/2);
      }else if(in[i]=='J')
	s=s[s.size()-1]+s.substr(0,s.size()-1);
      else if(in[i]=='M'){
	rep(j,s.size())if(isdigit(s[j])){
	  s[j]++;
	  if(s[j]>'9')s[j]='0';
	}
      }else if(in[i]=='P'){
	rep(j,s.size())if(isdigit(s[j])){
	  s[j]--;
	  if(s[j]<'0')s[j]='9';
	}
      }
      //cout<<s<<endl;
    }
    cout<<s<<endl;
  }

}

C++: #include <bits/stdc++.h>

using namespace std;

int main()
{
    int n;
    
    scanf("%d", &n);
    
    while (n--){
        char s[128], tmp[128];
        string t;
        scanf("%s", s);
        scanf("%s", tmp);
        
        t = (string)tmp;
        
        for (int i = strlen(s) - 1; i >= 0; i--){
            if (s[i] ==  'J')
                t = t[t.size() - 1] + t.substr(0, t.size() - 1);
            else if (s[i] == 'C')
                t = t.substr(1, t.size() - 1) + t[0];
            else if (s[i] == 'E'){
                string t1 = t.substr(0, t.size() / 2), t2 = t.substr((t.size() + 1) / 2, t.size() / 2);
                string e = "";
                t = t2 + ((t.size() & 1) ? string(1, t[t.size() / 2]) : e) + t1;
            }
            else if (s[i] == 'A')
                reverse(t.begin(), t.end());
            else if (s[i] ==  'P'){
                for (int j = 0; j < t.size(); j++){
                    if (isdigit(t[j])){
                        if (t[j] == '0') t[j] = '9';
                        else t[j]--;
                    }
                }
            }
            else {
                for (int j = 0; j < t.size(); j++){
                    if (isdigit(t[j])){
                        if (t[j] == '9') t[j] = '0';
                        else t[j]++;
                    }
                }
            }
        }
        printf("%s\n", t.c_str());
    }
    
    return (0);
}