Question

When president and vice president are not available?

Answer 1

Answer:

In such an eventuality, the chief justice—or in his absence, the senior most judge of the Supreme Court of India available—discharges the functions of the president until a newly elected President enters upon his office or a newly elected Vice-president begins to act as President under Article 65 of the constitution,

(i think this is your answer)

Answer 2

The United States Presidential Succession Act is a federal statute establishing the presidential line of succession.[1] Article II, Section 1, Clause 6 of the United States Constitution authorizes Congress to enact such a statute:

Congress may by Law provide for the Case of Removal, Death, Resignation or Inability, both of the President and Vice President, declaring what Officer shall then act as President, and such Officer shall act accordingly, until the Disability be removed, or a President shall be elected.[2]

Congress has enacted a Presidential Succession Act on three occasions: 1792 (1 Stat. 239), 1886 (24 Stat. 1), and 1947 (61 Stat. 380). The 1947 Act was last revised in 2006.

Although none of these succession acts have ever been invoked, an invocation was a distinct possibility on several occasions. However, the future likelihood that a person in the line of succession beyond the vice president will be called upon under normal circumstances to be acting president has diminished greatly due to the Twenty-fifth Amendment's provision for filling vice presidential vacancies.[3]