for(i=0;i<a;i++)
{
    if(x[i]>='A'&&x[i]<='z')
    {
        if(x[i]>='A'&&x[i]<'Z'||x[i]>='a'&&x[i]<'z')
            {
                x[i]=x[i]+1;
            }
            else if(x[i]=='z'||x[i]=='Z')
            {
                x[i]=x[i]-25;
            }
            
    }
}