C++ :

#include<cstdio>
#include<cstring>
#include<iostream>
#include<cmath>
using namespace std;
#define N 30010
int f[N],c[N],b[N];
int n;
void readln(int &x,int &y){
	x = y = 0;
	char ch = getchar();
	do{
		ch = getchar();
		if (isdigit(ch)) x = x * 10 + ch - 48;
	}while (isdigit(ch));
	do{
		ch = getchar();
		if (isdigit(ch)) y = y * 10 + ch - 48;
	}while (isdigit(ch));
	return;
}


int find_Fa(int x){
	int i = x;
	while (f[i] != i) i = f[i];
	int ff = i;
	i = x;
	int j;
	int next;
	while (i != ff){
		next = f[i];
		f[i] = ff;
		j = next;
		do{
			b[i] += b[j];
			j = f[j];
		}while (f[j] != j);
		i = next;
	}
	return ff;
}

void moveship(int x,int y){
	int fx = find_Fa(x),fy = find_Fa(y);
	f[f[fx]] = fy;
	b[fx] = b[fx] + c[fy];
	c[fy] += c[fx];
	return;
}

void check(int x,int y){
	int fx = find_Fa(x),fy = find_Fa(y);
	if (fx != fy) puts("-1");
	else printf("%d\n",abs(b[x] - b[y]) - 1);
	return;
}

int main(){
	for (int i = 1; i < N ; i++) f[i] = i,c[i] = 1,b[i] = 0;
	scanf("%d",&n);
	getchar();
	char ch;
	int x,y;
	while (n--){
                getchar();
		ch = getchar();
		readln(x,y);
		switch (ch){
			case 'M': moveship(x,y);break;
			case 'C': check(x,y);break;
		}
	}
	return 0;
}

Pascal :

var
 father,before,long:array[0..30005] of longint;
 i,j,t,x,y,sx,sy:longint;
 s:char;
function get(x:longint):longint;
var
 f:longint;
begin
 if father[x]=x then exit(x);
  f:=get(father[x]);
  before[x]:=before[x]+before[father[x]];
  father[x]:=f;
  get:=f;
end;
procedure init;
begin
 readln(t);
 for i:=1 to 30000 do begin father[i]:=i; before[i]:=0; long[i]:=1;end;
end;
procedure work;
begin
 for i:=1 to t do
  begin
   readln(s,x,y);
   if s='M' then
    begin
     sx:=get(x);
     sy:=get(y);
     father[sx]:=sy;
     before[sx]:=long[sy];
     long[sy]:=long[sy]+long[sx];
    end;
  if s='C' then
   begin
    sx:=get(x);
    sy:=get(y);
    if sx<>sy then j:=-1
     else j:=abs(before[x]-before[y])-1;
    writeln(j);
   end;
   end;
 end;
begin
 init;
 work;
 
end.