Caesar Cipher [Encoder & Decoder)

#include<stdio.h>
#include<string.h>
int main()
{
    char inp[100]={0}, cdr[]="AAEEIIOOUUAABCDFGHJKLMNPQRSTVWXYZBCaaeeiioouuaabcdfghjklmnpqrstvwxyzbc";
    int c,i,j,len;
X:
    printf("Enter String: ");
    gets(inp);
    len=strlen(inp);

    printf("Enter 1 to Encode\nEnter 2 to Decode\nEnter 0 to Exit\nEnter Your Choice: ");
    scanf("%d",&c);

    if(c==1)
    {
        for(i=0 ; i<len ; i++)
        {
            if((inp[i]<65) || (inp[i]>122) || (inp[i]>90 && inp[i]<97))
                    printf("%c", inp[i]);
            else
                for(j=0 ; j<64 ; j++)
                    if(inp[i]==cdr[j])
                    {
                        printf("%c",cdr[j+2]);
                        break;
                    }
        }
        printf("\n");
        goto X;
    }
    else if(c==2)
    {
        for(i=0 ; i<len ; i++)
        {
            if((inp[i]<65) || (inp[i]>122) || (inp[i]>90 && inp[i]<97))
                    printf("%c", inp[i]);
            else
                for(j=2 ; j<68 ; j++)
                {
                    if(j==35)
                        j=37;
                    if(inp[i]==cdr[j])
                    {
                        printf("%c",cdr[j-2]);
                        break;
                    }
                }
        }
        printf("\n");
        goto X;
    }
    else if(c==0)
        goto Z;
    else
    {
        printf("Wrong input. Try Again\n\n");
        goto X;
    }
Z:
        return 0;
}