Arbiter Login

#include<bits/stdc++.h>
using namespace std;

int main()
{
    int t, x=1;
    string pas, in;
    scanf("%d", &t);
    while (t--) {
        cin>>pas>>in;
        printf("Case %d: ", x++);
        if (in==pas) {
            printf("Login successful.\n");
        }
        else {
            printf("Wrong password.");
            string k=in, n=pas, z=pas;
            int d=in.length(), l=pas.length();
            for (int i=0; i<d; i++) {
                if (k[i]>=65 && k[i]<=90)
                    k[i]=k[i]+32;
                else if (k[i]>=97 && k[i]<=122)
                    k[i]=k[i]-32;
            }
            for (int i=0; i<l; i++) {
                if (n[i]>='0' && n[i]<='9')
                    n.erase(n.begin()+i);
            }
            for (int i=0; i<l; i++) {
                if (z[i]>=65 && z[i]<=90)
                    z[i]=z[i]+32;
                else if (z[i]>=97 && z[i]<=122)
                    z[i]=z[i]-32;
                else if (z[i]>='0' && z[i]<='9')
                    z.erase(z.begin()+i);
            }
            if (k==pas) {
                printf(" Please, check your caps lock key.\n");
            }
            else if (n==in) {
                printf(" Please, check your num lock key.\n");
            }
            else if (z==in) {
                printf(" Please, check your caps lock and num lock keys.\n");
            }
            else
                printf("\n");
        }
    }
    return 0;
}