The Jallianwala Bagh massacre, also known as the Amritsar massacre, took place on 13 April 1919. A large but peaceful crowd had gathered at the Jallianwala Bagh in Amritsar, Punjab to protest against the arrest of pro-Indian independence leaders Dr. Saifuddin Kitchlu and Dr. Satya Pal. In response to the public gathering, the British Brigadier-General Dyer surrounded the Bagh with his soldiers. The Jallianwala Bagh could only be exited on one side, as its other three sides were enclosed by buildings. After blocking the exit with his troops, he ordered them to shoot at the crowd, continuing to fire even as protestors tried to flee. The troops kept on firing until their ammunition was exhausted. At least 379 people were killed and over 1,200 other people were injured of whom 192 were seriously injured.

Responses polarized both the British and Indian peoples. Eminent author Rudyard Kipling declared at the time that Dyer “did his duty as he saw it”. This incident shocked Rabindranath Tagore (the first Indian and Asian Nobel laureate) to such an extent that he renounced his knighthood and stated that “such mass murderers aren’t worthy of giving any title to anyone”.

The massacre caused a re-evaluation by the British Army of its military role against civilians to minimal force whenever possible, although later British actions during the Mau Mau insurgencies in Kenya have led historian Huw Bennett to note that the new policy was not always carried out. The army was retrained and developed less violent tactics for crowd control.

The level of casual brutality, and lack of any accountability, stunned the entire nation, resulting in a wrenching loss of faith of the general Indian public in the intentions of the UK. The ineffective inquiry, together with the initial accolades for Dyer, fuelled great widespread anger against the British among the Indian populace, leading to the Non-cooperation movement of 1920–22. Some historians consider the episode a decisive step towards the end of British rule in India. Britain never formally apologised for the massacre but expressed “regret” in 2019.

On Sunday, 13 April 1919, Dyer, convinced a major insurrection could take place, banned all meetings. This notice was not widely disseminated, and many villagers gathered in the Bagh to celebrate the important Hindu and Sikh festival of Baisakhi, and peacefully protest the arrest and deportation of two national leaders, Satyapal and Saifuddin Kitchlew. Dyer and his troops entered the garden, blocking the main entrance behind them, took up position on a raised bank, and with no warning opened fire on the crowd for about ten minutes, directing their bullets largely towards the few open gates through which people were trying to flee, until the ammunition supply was almost exhausted. The following day Dyer stated in a report that “I have heard that between 200 and 300 of the crowd were killed. My party fired 1,650 rounds”.

At 9:00 on the morning of 13 April 1919, the traditional festival of Baisakhi. Reginald Dyer, the acting military commander for Amritsar and its environs, proceeded through the city with several city officials, announcing the implementation of a pass system to enter or leave Amritsar, a curfew beginning at 20:00 that night and a ban on all processions and public meetings of four or more persons. The proclamation was read and explained in English, Urdu, Hindi, and Punjabi, but few paid it any heed or appear to have learned of it later. Meanwhile, local police had received intelligence of the planned meeting in the Jallianwala Bagh through word of mouth and plainclothes detectives in the crowds. At 12:40, Dyer was informed of the meeting and returned to his base at around 13:30 to decide how to handle it.

By mid-afternoon, thousands of Indians had gathered in the Jallianwala Bagh (garden) near the Harmandir Sahib in Amritsar. Many who were present had earlier worshipped at the Golden Temple, and were passing through the Bagh on their way home. The Bagh was (and remains today) an open area of six to seven acres, roughly 200 yards by 200 yards in size, and surrounded on all sides by walls roughly 10 feet in height. Balconies of houses three to four stories tall overlooked the Bagh, and five narrow entrances opened onto it, several with lockable gates. During the rainy season, it was planted with crops, but served as a local meeting and recreation area for much of the year. In the center of the Bagh was a samadhi (cremation site) and a large well partly filled with water which measured about 20 feet in diameter.

Apart from pilgrims, Amritsar had filled up over the preceding days with farmers, traders, and merchants attending the annual Baisakhi horse and cattle fair. The city police closed the fair at 14:00 that afternoon, resulting in a large number of people drifting into the Jallianwala Bagh.

Dyer arranged for an aeroplane to overfly the Bagh and estimate the size of the crowd, that he reported was about 6,000, while the Hunter Commission estimates a crowd of 10,000 to 20,000 had assembled by the time of Dyer’s arrival. Colonel Dyer and Deputy Commissioner Irving, the senior civil authority for Amritsar, took no actions to prevent the crowd assembling, or to peacefully disperse the crowds. This would later be a serious criticism levelled at both Dyer and Irving.

An hour after the meeting began as scheduled at 17:30, Colonel Dyer arrived at the Bagh with a group of ninety soldiers from the Gurkha Rifles, the 54th Sikhs and the 59th Sind Rifles. Fifty of them were armed with .303 Lee–Enfield bolt-action rifles. It is not clear whether Dyer had specifically chosen troops from that ethnic group due to their proven loyalty to the British or that they were simply the Sikh and non-Sikh units most readily available. He had also brought two armoured cars armed with machine guns; however, the vehicles were left outside, as they were unable to enter the Bagh through the narrow entrances. The Jallianwala Bagh was surrounded on all sides by houses and buildings and had only five narrow entrances, most kept permanently locked. The main entrance was relatively wide, but was guarded heavily by the troops backed by the armoured vehicles.

Dyer, without warning the crowd to disperse, blocked the main exits. He stated later that this act “was not to disperse the meeting but to punish the Indians for disobedience.” Dyer ordered his troops to begin shooting toward the densest sections of the crowd in front of the available narrow exits, where panicked crowds were trying to leave the Bagh. Firing continued for approximately ten minutes. Cease-fire was ordered only when ammunition supplies were almost exhausted, after approximately 1,650 rounds were spent.

Apart from the many deaths directly from the shooting, a number of people died of crushing in the stampedes at the narrow gates or by jumping into the solitary well on the compound to escape the shooting. A plaque, placed at the site after independence, states that 120 bodies were removed from the well. The wounded could not be moved from where they had fallen, as a curfew was declared, and more who had been injured then died during the night.

A recursive algorithm calls itself which usually passes the return value as a parameter to the algorithm again. This parameter is the input while the return value is the output. Recursive algorithm is a method of simplification that divides the problem into sub-problems of the same nature. The result of one recursion is the input for the next recursion. The repletion is in the self-similar fashion. The algorithm calls itself with smaller input values and obtains the results by simply performing the operations on these smaller values. Generation of factorial, Fibonacci number series are the examples of recursive algorithms.

Properties

A recursive function can go infinite like a loop. To avoid infinite running of recursive function, there are two properties that a recursive function must have −
• Base criteria − There must be at least one base criteria or condition, such that, when this condition is met the function stops calling itself recursively.
• Progressive approach − The recursive calls should progress in such a way that each time a recursive call is made it comes closer to the base criteria.
Implementation

Many programming languages implement recursion by means of stacks. Generally, whenever a function (caller) calls another function (Calle) or itself as calle, the caller function transfers execution control to the Calle. This transfer process may also involve some data to be passed from the caller to the calle.
This implies, the caller function has to suspend its execution temporarily and resume later when the execution control returns from the calle function. Here, the caller function needs to start exactly from the point of execution where it puts itself on hold. It also needs the exact same data values it was working on. For this purpose, an activation record (or stack frame) is created for the caller function.