CPCARROS SPOJ Br AC

#include <stdio.h>
#include <algorithm>
#include <string.h>
#include <ctype.h>
using namespace std;

char isa[10];
char martin[10];
int c;
char probChar[]={'A','C','M','I','P'};
long long newP[] = {21*21*21*21*10*10LL,
        21*21*21*10*10LL,
        21*21*10*10LL,
        21*10*10LL,
        10*10LL,
        10LL,
        1LL};
long long oldP[] = {26*26*10*10*10*10LL,
        26*10*10*10*10LL,
        10*10*10*10LL,
        10*10*10LL,
        10*10LL,
        10LL,
        1LL};
long long letUntil[30];

bool goodChar(char a) {
    if (a<'A' || a>'Z')
        return false;
    for (int i=0; i<5; i++)
        if (a==probChar[i])
            return false;
    return true;
}

bool valid(char* plate) {
    if (isalpha(plate[4])) {
        for (int i=0; i<5; i++)
            if (!goodChar(plate[i]))
                return false;

        for (int i=5; i<7; i++)
            if (!isdigit(plate[i]))
                return false;
    }
    else {
        for (int i=0; i<3; i++)
            if (plate[i]<'A' || plate[i]>'Z')
                return false;

        for (int i=3; i<7; i++)
            if (!isdigit(plate[i]))
                return false;
    }

    return true;
}

long long plateNum(const char* plate) {
    long long num=0;

    if (isalpha(plate[4])) {
        num+=plateNum("ZZZ9999")+1;

        for (int i=0; i<5; i++)
            num+=(letUntil[plate[i]-'A']*newP[i]);
        for (int i=5; i<7; i++)
            num+=((plate[i]-'0')*newP[i]);
    }
    else {
        for (int i=0; i<3; i++)
            num+=((plate[i]-'A')*oldP[i]);
        for (int i=3; i<7; i++)
            num+=((plate[i]-'0')*oldP[i]);
    }

    return num;
}

int main() {
    long long sum=0;
    for (char i='A'; i<='Z'; i++)
        if (goodChar(i)) letUntil[i-'A']=sum++;

    while (1) {
        scanf(" %s %s %d", martin, isa,&c);
        if (!strcmp(martin,"*") && !strcmp(isa,"*") && !c)
            break;

        if (!valid(isa)) {
            printf("N\n");
            continue;
        }

        long long nIsa = plateNum(isa);
        long long nMartin = plateNum(martin);

        if (nIsa-nMartin>0 && nIsa-nMartin<=c)
            printf("Y\n");
        else printf("N\n");
    }

    return 0;
}