while i < j:
    if x[i] == a:
        cnt1 += 1
        i += 1
    else:
        print(cnt1,end='')
        print(a,end='')

        if x[i] == b:
            cnt2 += 1
            i += 1
        else:
            print(cnt2,end='')
            print(b,end='')
            if x[i] == c:
                cnt3 += 1
                i += 1
            else:
                print(cnt3,end='')
                print(c,end='')