Chapter 206: Abacus Challenge to the Calculator: New vs. Old Computation Showdown

The train's arrival noise had just faded, and the Siheyuan still held a hush. People drifted out of the houses in small groups; some carried a Meal Ticket bowl and squatted at the gate to eat, others brought out small stools and sat in the Courtyard to enjoy the breeze. Jia Dongxu, having just shouldered a display rack back, placed his things in the corner, wiped his sweat, was about to pour water to drink when he heard San Daye shout from the center of the Courtyard.

"Everyone, come over and take a look! Today I have something to tell you!"

Everyone looked up; San Daye stood by a stone Desk, cradling a red‑wood abacus whose frame was polished to a shine, the beads lined up neatly, clearly a well‑worn old piece. He placed the abacus on the Desk, producing a crisp "Snap" sound.

"You all keep talking about computers and calculators these days, as if you couldn't do arithmetic without those gadgets," San Daye said in a loud voice. "I ask you, if you count π to a million decimal places, who among you can recite it? If a machine can compute it, then I'll believe it truly has skill."

Someone in the crowd laughed, "San Daye, are you challenging the calculator?"

"It's not a challenge, it's a comparison," San Daye glared. "Who dares? Bring your electronic calculators and compute together with my abacus; see who gets the result first, who computes more accurately."

Jia Dongxu, hearing this, became interested. He set down his water cup, walked over and said, "San Daye, you really want to compute π? A thousand places is already enough of a challenge; forget a million."

"I don't need to finish a million," San Daye hummed, "We'll start with a thousand places. If you dare to accept, I'll dare to strike the beads."

Someone nearby heckled, "A competition! This is getting interesting!"

Jia Dongxu didn't hesitate, turned back into the house, and pulled out the electronic calculator he had brought from the exhibition. It was a new model with a Screen, capable of continuous computation, a test unit he had specially borrowed from the factory. He placed it on the Desk, pressed the power button, and the Screen lit up.

"Fine, I accept," Jia Dongxu said, "Let's be fair: start together, compute up to the thousandth decimal place; whoever makes a single mistake loses."

San Daye nodded, rested both hands on the abacus, his fingers lightly flicking a few beads to test the feel. "Ready."

The onlookers kept gathering. Sha Zhu, after finishing his Meal Ticket, passed by, toothpick in mouth, and came over: "Yo, abacus versus electronic calculator? This show is entertaining."

"What do you know," San Daye gave him a cold stare, "This is a skill, not a circus act."

"Begin!" someone shouted.

Jia Dongxu lowered his head, stared at the calculator, his hands rapidly entering the startup program. Numbers quickly scrolled on the Screen, line after line cascading down. His eyes tracked the Data Stream, occasionally checking whether the initial values were correct.

San Daye's side grew even quieter. He closed his eyes, muttered a mantra under his breath, his fingers suddenly jerking; the abacus beads went "Pop" and "Snap", raining down densely. He steadied the frame with his left hand, his right hand's five fingers flicked; each flick was crisp, the beads striking the end with a clear "Clack" sound.

The first hundred places were computed smoothly. Jia Dongxu's machine output steadily, and San Daye kept pace. Someone with paper and pen cross‑checked the values against a reference book and found no errors on either side.

"Impressive," someone muttered, "San Daye's mind computes faster than even our kids."

At three hundred places, San Daye's forehead began to sweat. He exhaled, took a sip of water, and kept striking the beads. His fingers grew a bit sore, but he gritted his teeth and persisted, repeatedly reciting the carry rules in his mouth as if keeping his own rhythm.

Jia Dongxu suddenly frowned. The numbers on the Screen paused, jumped a few positions, then began to flicker. He tapped the machine, "What's wrong?"

No one answered. He pressed a few function keys again; the Screen flashed twice, emitting a faint burnt smell.

"Broken?" Sha Zhu peeked.

"Impossible!" Jia Dongxu quickly powered off, opened the back cover and felt the circuit board, "It was fine a moment ago, why is it smoking now?"

Sure enough, the edge of the circuit board was slightly blackened. He sighed, "Probably jolted during transport; a solder joint came loose."

The crowd erupted.

"Whoa, it gave up before the competition even finished?"

"Seems the machine isn't reliable either."

San Daye listened, gradually halting his movements. He looked at the smoking calculator, then lowered his head to glance at his abacus, exhaling, "What was I saying? Even the most advanced gear has its moments of failure. My abacus has been in use for forty years and has never missed a bead."

Jia Dongxu retorted, "That's not a technical issue, it's a matter of equipment quality."

Before the words finished, He Yushui stepped out of the house, cradling a box in her hands. She walked to the Desk, opened the box, revealing a strange device—shaped like an abacus but with a small panel beneath, bearing a few buttons and a tiny numeric Screen.

"San Daye," she said, "I heard you explain the carry method last night and found it especially logical. I tried embedding your algorithm into a small circuit and made an aid. It doesn't compute for you, but it records the carries, saving you effort."

San Daye was stunned, "You… you can still do this?"

"Please try," He Yushui placed the device gently on the Desk, pressed the power button. The Screen lit up, displaying "Standby".

San Daye hesitantly reached out, tapped the Screen, then brushed the adjacent abacus part. He tried moving a bead, and the Screen instantly displayed a number: "1".

He tried several addition and subtraction operations; after each, the Screen updated the result in sync and even prompted whether a carry was needed.

"This… this is like giving me a little assistant?" San Daye's voice trembled slightly.

"Yes," He Yushui smiled, "The old method plus the new component runs faster and is less error‑prone."

Jia Dongxu leaned in to examine the circuit design, exclaiming, "You used the most basic logic‑gate combination, yet you managed to translate the abacus rules into electrical signals?"

"I referenced the control module schematics Zhao Jianguo left earlier," He Yushui said, "The principle is similar: converting human thought steps into commands a machine can understand."

San Daye said nothing, head lowered, his fingers sliding back and forth on the abacus. Suddenly he moved a string of numbers, reciting the mantra, and the Screen simultaneously displayed the result. He repeated the test several times, each time correct.

Finally, he lifted his head, his eyes a little red, "My father, when teaching me to use the abacus, said the craft must not be abandoned. He also said one must look forward. Today I realized that even old things can take on a new form."

The surrounding people fell silent.

Sha Zhu scratched his head, "Why do I feel this is warmer in the heart than watching a movie?"

Jia Dongxu patted He Yushui's shoulder, "If you roll this out, accountants will save a huge hassle."

"I still want to refine it," He Yushui said, "For example, add storage so it can keep common formulas and print results. In the future, collecting water and electricity fees in the Courtyard, recording work points, won't need to be handwritten."

"Then you need a name," someone shouted.

"What should we call it?" another asked.

"Let's call it 'Siheyuan Suan' then," San Daye suddenly said, "It's something the people here thought up and built together."

Applause erupted instantly.

The night breeze gently brushed the Courtyard, bringing a hint of coolness. Children gathered around the Desk to look at the new device, asking curious questions. Adults discussed whether each production team could be equipped with one, and some even suggested sending it to the street for exhibition.

Jia Dongxu crouched on the ground, holding a small screwdriver, repairing the calculator while chatting with He Yushui about circuit stability. He said, "Next time don't use those cheap capacitors; they burn easily. Switch to ceramic ones; they withstand high temperature."

"Got it," He Yushui nodded, "I also want to add battery protection to prevent sudden power loss from losing data."

San Daye sat on a stone stool, cradling the hybrid computing device, rubbing its edge repeatedly. He said nothing, but a smile lingered at the corner of his mouth.

Footsteps came from the Courtyard Gate; someone entered carrying an Oil Lamp, saying they'd heard about a new‑technology demonstration here and came specifically to see. Another neighbor brought out several bowls of mung bean soup from the Kitchen, saying it was to cool everyone down.

The bustle continued until after nine o'clock in the evening.

Finally, He Yushui took out a sheet of paper and began recording the most common calculation problems everyone faced: computing work points, reconciling accounts, measuring cloth, weighing grain… She noted each item, saying a more practical version would be made based on these needs.

"We can trial‑run it tomorrow," she said, "First we'll use it in the Courtyard; if all goes well, we'll roll it out further."

Jia Dongxu looked up at the sky, "This matter needs to be reported upward."

"No rush," He Yushui lowered her head to write, "We'll steady our own steps first."

The crowd gradually dispersed, some went back inside, others were still discussing. Before leaving, San Daye held the device tightly, as if guarding some treasure.

Dong Xu fixed the calculator and restarted it. The Screen lit up, Data Normal. He was about to speak when he suddenly saw the first line He Yushui had written on the paper:

「Community Maintenance Registration System Test Version——Go live tomorrow。」

He froze for a moment, then looked up at her.

She was folding the paper and slipping it into her pocket, saying: 「The first task, fix the water pump. 」