Question: Who was the first president of the country that borders Eritrea to the southeast?

full_context: Document 1: Republic of the Congo: On March 27, 2015 Sassou Nguesso announced that his government would hold a referendum to change the country's 2002 constitution and allow him to run for a third consecutive term in office. On October 25 the government held a referendum to allow Sassou Nguesso to run in the next election. The government claimed that the proposal as approved by 92 percent of voters with 72 percent of eligible voters participating. The opposition, who had boycotted the referendum claimed that the government's statistics were false and that the vote was a sham.
Document 2: Guinea-Bissau: In June 2005, presidential elections were held for the first time since the coup that deposed Ialá. Ialá returned as the candidate for the PRS, claiming to be the legitimate president of the country, but the election was won by former president João Bernardo Vieira, deposed in the 1999 coup. Vieira beat Malam Bacai Sanhá in a runoff election. Sanhá initially refused to concede, claiming that tampering and electoral fraud occurred in two constituencies including the capital, Bissau.
Document 3: Somalis: Somali people in the Horn of Africa are divided among different countries (Somalia, Djibouti, Ethiopia, and northeastern Kenya) that were artificially and some might say arbitrarily partitioned by the former imperial powers. Pan-Somalism is an ideology that advocates the unification of all ethnic Somalis once part of Somali empires such as the Ajuran Empire, the Adal Sultanate, the Gobroon Dynasty and the Dervish State under one flag and one nation. The Siad Barre regime actively promoted Pan-Somalism, which eventually led to the Ogaden War between Somalia on one side, and Ethiopia, Cuba and the Soviet Union on the other.
Document 4: Eritrea: The creation of modern-day Eritrea is a result of the incorporation of independent, distinct kingdoms and sultanates (for example, Medri Bahri and the Sultanate of Aussa) eventually resulting in the formation of Italian Eritrea. In 1947 Eritrea became part of a federation with Ethiopia, the Federation of Ethiopia and Eritrea. Subsequent annexation into Ethiopia led to the Eritrean War of Independence, ending with Eritrean independence following a referendum in April 1993. Hostilities between Eritrea and Ethiopia persisted, leading to the Eritrean–Ethiopian War of 1998–2000 and further skirmishes with both Djibouti and Ethiopia.
Document 5: Eritrea: During the Middle Ages, the Eritrea region was known as Medri Bahri ("sea-land"). The name Eritrea is derived from the ancient Greek name for Red Sea (Ἐρυθρὰ Θάλασσα Erythra Thalassa, based on the adjective ἐρυθρός erythros "red"). It was first formally adopted in 1890, with the formation of Italian Eritrea (Colonia Eritrea). The territory became the Eritrea Governorate within Italian East Africa in 1936. Eritrea was annexed by Ethiopia in 1953 (nominally within a federation until 1962) and an Eritrean Liberation Front formed in 1960. Eritrea gained independence following the 1993 referendum, and the name of the new state was defined as State of Eritrea in the 1997 constitution.[citation needed]
Document 6: Republic of the Congo: Following the revision of the French constitution that established the Fifth Republic in 1958, the AEF dissolved into its constituent parts, each of which became an autonomous colony within the French Community. During these reforms, Middle Congo became known as the Republic of the Congo in 1958 and published its first constitution in 1959. Antagonism between the pro-Opangault Mbochis and the pro-Youlou Balalis resulted in a series of riots in Brazzaville in February 1959, which the French Army subdued.
Document 7: Egypt: Egypt (i/ˈiːdʒɪpt/; Arabic: مِصر‎ Miṣr, Egyptian Arabic: مَصر Maṣr, Coptic: Ⲭⲏⲙⲓ Khemi), officially the Arab Republic of Egypt, is a transcontinental country spanning the northeast corner of Africa and southwest corner of Asia, via a land bridge formed by the Sinai Peninsula. It is the world's only contiguous Eurafrasian nation. Most of Egypt's territory of 1,010,408 square kilometres (390,000 sq mi) lies within the Nile Valley. Egypt is a Mediterranean country. It is bordered by the Gaza Strip and Israel to the northeast, the Gulf of Aqaba to the east, the Red Sea to the east and south, Sudan to the south and Libya to the west.
Document 8: Eritrea: Eritrea is a multilingual country. The nation has no official language, as the Constitution establishes the "equality of all Eritrean languages". However, Tigrinya serves as the de facto language of national identity. With 2,540,000 total speakers of a population of 5,254,000 in 2006, Tigrinya is the most widely spoken language, particularly in the southern and central parts of Eritrea. Modern Standard Arabic and English serve as de facto working languages, with the latter used in university education and many technical fields. Italian, the former colonial language, is widely used in commerce and is taught as a second language in schools, with a few elderly monolinguals.
Document 9: Eritrea: Eritrea can be split into three ecoregions. To the east of the highlands are the hot, arid coastal plains stretching down to the southeast of the country. The cooler, more fertile highlands, reaching up to 3000m has a different habitat. Habitats here vary from the sub-tropical rainforest at Filfil Solomona to the precipitous cliffs and canyons of the southern highlands. The Afar Triangle or Danakil Depression of Eritrea is the probable location of a triple junction where three tectonic plates are pulling away from one another.The highest point of the country, Emba Soira, is located in the center of Eritrea, at 3,018 meters (9,902 ft) above sea level.
Document 10: Somalis: A referendum was held in neighboring Djibouti (then known as French Somaliland) in 1958, on the eve of Somalia's independence in 1960, to decide whether or not to join the Somali Republic or to remain with France. The referendum turned out in favour of a continued association with France, largely due to a combined yes vote by the sizable Afar ethnic group and resident Europeans. There was also widespread vote rigging, with the French expelling thousands of Somalis before the referendum reached the polls. The majority of those who voted no were Somalis who were strongly in favour of joining a united Somalia, as had been proposed by Mahmoud Harbi, Vice President of the Government Council. Harbi was killed in a plane crash two years later. Djibouti finally gained its independence from France in 1977, and Hassan Gouled Aptidon, a Somali who had campaigned for a yes vote in the referendum of 1958, eventually wound up as Djibouti's first president (1977–1991).
Document 11: Djibouti: Djibouti ( (listen) jih-BOO-tee; Afar: Yibuuti, Arabic: جيبوتي‎ Jībūtī, French: Djibouti, Somali: Jabuuti, officially the Republic of Djibouti) is a country located in the Horn of Africa. It is bordered by Eritrea in the north, Ethiopia in the west and south, and Somalia in the southeast. The remainder of the border is formed by the Red Sea and the Gulf of Aden at the east. Djibouti occupies a total area of 23,200 km2 (8,958 sq mi). The state of Djibouti is predominantly inhabited by two ethnic groups, the Somali and the Afar people, the Somalis being the major ethnic group of the country.
Document 12: Central African Republic: By 1990, inspired by the fall of the Berlin Wall, a pro-democracy movement arose. Pressure from the United States, France, and from a group of locally represented countries and agencies called GIBAFOR (France, the USA, Germany, Japan, the EU, the World Bank, and the UN) finally led Kolingba to agree, in principle, to hold free elections in October 1992 with help from the UN Office of Electoral Affairs. After using the excuse of alleged irregularities to suspend the results of the elections as a pretext for holding on to power, President Kolingba came under intense pressure from GIBAFOR to establish a "Conseil National Politique Provisoire de la République" (Provisional National Political Council, CNPPR) and to set up a "Mixed Electoral Commission", which included representatives from all political parties.[citation needed]
Document 13: Somalis: British Somaliland became independent on 26 June 1960 as the State of Somaliland, and the Trust Territory of Somalia (the former Italian Somaliland) followed suit five days later. On 1 July 1960, the two territories united to form the Somali Republic, albeit within boundaries drawn up by Italy and Britain. A government was formed by Abdullahi Issa Mohamud and Muhammad Haji Ibrahim Egal other members of the trusteeship and protectorate governments, with Haji Bashir Ismail Yusuf as President of the Somali National Assembly, Aden Abdullah Osman Daar as the President of the Somali Republic and Abdirashid Ali Shermarke as Prime Minister (later to become President from 1967 to 1969). On 20 July 1961 and through a popular referendum, the people of Somalia ratified a new constitution, which was first drafted in 1960. In 1967, Muhammad Haji Ibrahim Egal became Prime Minister, a position to which he was appointed by Shermarke. Egal would later become the President of the autonomous Somaliland region in northwestern Somalia.
Document 14: Eritrea: In the 1950s, the Ethiopian feudal administration under Emperor Haile Selassie sought to annex Eritrea and Italian Somaliland. He laid claim to both territories in a letter to Franklin D. Roosevelt at the Paris Peace Conference and at the First Session of the United Nations. In the United Nations, the debate over the fate of the former Italian colonies continued. The British and Americans preferred to cede all of Eritrea except the Western province to the Ethiopians as a reward for their support during World War II. The Independence Bloc of Eritrean parties consistently requested from the UN General Assembly that a referendum be held immediately to settle the Eritrean question of sovereignty.
Document 15: Eritrea: Eritrea (/ˌɛrᵻˈtreɪ.ə/ or /ˌɛrᵻˈtriːə/;, officially the State of Eritrea, is a country in East Africa. With its capital at Asmara, it is bordered by Sudan in the west, Ethiopia in the south, and Djibouti in the southeast. The northeastern and eastern parts of Eritrea have an extensive coastline along the Red Sea. The nation has a total area of approximately 117,600 km2 (45,406 sq mi), and includes the Dahlak Archipelago and several of the Hanish Islands. Its name Eritrea is based on the Greek name for the Red Sea (Ἐρυθρὰ Θάλασσα Erythra Thalassa), which was first adopted for Italian Eritrea in 1890.
ground_truth: Hassan Gouled Aptidon
sub_queries: What country borders Eritrea in the southeast? Answer: Djibouti
Who was the first president of Djibouti ? Answer: Hassan Gouled Aptidon