Chapter 133: Variables and Margin

The cicadas wrapped Qingshi Village in July in a sticky shell. The cross-breeze through the main room had stopped. Only the old ceiling fan creaked overhead, its blades coated in thick dust; with every turn, a fine ring of powder drifted down. Lin Chen sat beside the square table, his left ankle propped on an old towel washed stiff with use. The wound had scabbed over, but the edges were still dark red, and the tissue beneath had begun to stiffen from being immobilized so long. He tried shifting his weight onto it. A wave of sore resistance rose from the muscles in his calf. He eased back and lowered his head to the book in his hands.

C Programming Language Design. White characters on a blue cover. The spine had been wrapped twice in clear tape. He had picked it up for two yuan at the used-book stall by County No. 2 High School. The stall owner, a retired physics teacher, had shoved it into his hands before packing up and said, “Even if you get reassigned, it’s not a bad line of work. You won’t starve in it later.” Lin Chen had said nothing, only handed over the money. Now the book lay open beside his scratch paper, its corners curled from repeated turning.

There was no computer. That was the reality. But he did not intend to wait.

He picked up a pencil and wrote the first line of code on the paper: #include <stdio.h>. The tip moved across the page with a faint rasp. He wrote line by line. Define variables. Declare functions. Write loops. Write conditions. After each section, he closed his eyes and simulated the machine’s execution in his head. How memory would be allocated. Where the pointer would point. How stack frames would be pushed and popped. When he ran into an infinite loop, he drew a red X on the page and marked the logical breakpoint. When an array went out of bounds, he worked through the edge conditions again. He broke programming down into math problems. Broke syntax down into rules. Broke error messages down into the red Xs in a workbook of wrong answers.

It was a clumsy method. But for him, it was the only path he could control. He did not need to see output on a screen right away. He only needed to confirm that the chain of his logic was closed. He turned to the chapter on pointers. The symbols on the page were packed tight. He picked up his pen and wrote in the margin: int *p; p = &a;. Pointer. Address. Dereference. He closed his eyes. In his mind he built a memory model: rows of continuous cells, an arrow pointing to one of them. Read. Modify. Release. The logic ran. No errors. No dead loops. Only a clear path of execution.

Footsteps sounded outside the main room. Wang Guiying came in carrying a basin of well water, a towel draped over her shoulder. She set the basin at the corner of the table, glanced at the towel under Lin Chen’s foot, then at the table full of scratch paper. She could not make sense of the symbols on it, but she knew what her son was busy with.

“The town postman said admission notices should be coming in these next few days.” Her voice was very soft, as if afraid of disturbing something. “Your father went to the credit union to ask. Tuition, dorm fees, miscellaneous fees. Altogether it comes to forty-two hundred.”

Lin Chen’s pen paused for a moment. Forty-two hundred. The number dropped like a stone into the logical model he had just built. He opened the ledger. On the latest page it read: cash the family could currently use, eight hundred. Gap: three thousand four hundred.

“No rush,” he said. His voice was level, without inflection. “First we wait for the notice. When it gets here, then we work out the route.”

Wang Guiying nodded and said nothing more. She turned and went to light the stove in the kitchen. Firewood crackled. The smell of hot oil mixed with the coolness of well water and slowly spread through the room. Lin Jianguo sat on the threshold, pinching half a cigarette between his fingers. Without turning around, he said, “Computers. I hear you have to stare at a screen all the time. Can your eyes take it?”

“They can,” Lin Chen answered.

He lowered his head and kept writing code. for (int i = 0; i < 10; i++). Loop ten times. Execute one instruction each time. Reality worked the same way. He did not need to leap to the finish in a single step. He only needed to calculate the margin in each step precisely.

Two in the afternoon. The sun at its harshest. Lin Chen closed the book, sorted the scratch paper in order, and clipped it into a hard folder. He stood. His left foot touched the ground. The pain was still there, but his gait had already formed a new muscular memory. Weight to the right, left leg dragging slightly, like an old machine that had been recalibrated. He walked to the courtyard wall and picked up the bamboo pole leaning against it. A rag was tied to the end. He reached it up to the clothesline under the eaves, hooked an old shirt, and pulled it down.

He needed to go into town. Not to buy books. Not to see a doctor.

To the post office.

Fifteen kilometers. The asphalt had softened in the heat, and there was a slight tackiness underfoot. He walked very slowly. Every two hundred steps, he stopped and shifted his weight to his right leg, giving the wound on his left foot a chance to air. Sweat ran from his temples, dripping onto his collar and spreading into dark patches. He did not wipe it away. He only stared at the road markers ahead. Calculating distance. Calculating time. Calculating margin.

Four ten in the afternoon. He reached the town post office. Faded business hours were taped to the glass door. He pushed it open and cool air mixed with the smell of old newspapers hit him in the face. Behind the counter sat an auntie in reading glasses. He handed over his exam admission slip and ID card.

“Please check the file for Lin Chen from Qingshi Village,” he said.

She tapped at the keyboard a few times. The screen glowed a dim blue. After searching for a while, she looked up. “It hasn’t arrived yet. The provincial capital batch usually doesn’t come down until mid-August. Yours is an adjustment into a second-tier university, so it may be even later. But the file has already been created in the system. Status is ‘waiting to be sent.’”

“Understood.” Lin Chen took back his documents and turned to leave.

He was not disappointed. Waiting was part of the process. He walked to the Xinhua Bookstore across the street. In the display window stood several bulky desktop computers. Flat CRT monitors. Tower cases gone gray-white with age. He stood outside the glass and looked at them for ten minutes. The screens were black. But he knew operating systems were running inside them. Compilers were running. The symbols he had written on paper could run there too.

He touched his pocket. Inside were three crumpled ten-yuan notes. Money he had earned over the past few days helping the old accountant sort through ledgers. Thirty yuan. Not enough to buy a used machine. Not even enough to rent computer time for a month. But he noted the notice pasted on the wall beside the bookstore: County Library Summer Computer Room Open. Student ID required. Two yuan per hour. Limited access. Reservation required. Daily hours: 9:00–11:00 a.m., 2:00–4:00 p.m.

He took out his notebook and wrote on a blank page: County Library computer room. Reservation rules. Opening hours. Transportation cost. Two yuan per hour. At most four hours per day. Monthly budget cap. He turned it into a table. Filled in the variables. Marked the constraints in red. Round-trip bus fare: four yuan. Lunch, compressed biscuits: two yuan. Fixed daily spending: six yuan. Funds currently available this month: thirty yuan. Reservable days: five. The remaining twenty-five days would have to be covered by part-time work.

He finished the table. The tip of his pen stopped.

Reality had no shortcut. Only decomposition.

On the way home, the sky darkened. The mountain silhouettes in the distance were stained a deep purple by the sunset. The wind carried the raw smell of rice paddies. He walked steadily. His left foot no longer tried to bear weight by force. Instead, he worked with the muscle wasting and found a new balance point. He knew the injury would not heal at once. The money would not appear at once. The computer would not appear at once. But the variables had already been listed. The margin was being calculated.

By the time he got home, the light in the main room was already on. Wang Guiying was stir-frying at the stove. Lin Jianguo was weaving a bamboo basket. Xiaoman lay on the threshold, drawing squares on the ground with chalk. Hearing footsteps, Xiaoman looked up, and his eyes lit at once.

“Brother.” He handed over a piece of paper.

On it was a square, boxy machine. Inside the screen, blue crayon filled the whole space with light. Beside it, in crooked handwriting, were the words: Big Brother’s Computer.

Lin Chen took it. The paper was thin, the crayon marks slightly blurred. He slipped it into the folder together with the scratch paper.

“Good drawing,” he said.

Xiaoman smiled, showing the gap where one tooth was missing.

Lin Chen sat down and switched on the desk lamp. Its dim yellow halo lit the tabletop. He opened C Programming Language Design to the chapter on file operations. The symbols on the page were densely packed. He picked up his pen and wrote in the blank space: FILE *fp; fp = fopen("data.txt", "r");. Open. Read. Close. He closed his eyes. In his mind he simulated disk seeking, the movement of the read head, the retrieval of sectors. The logic ran. No errors. Only a clear path of execution.

He opened his eyes and looked at the calendar on the wall. July 15. Forty-seven days until September 1.

He closed the book and capped the pen. The movement was slow, but steady.

Tomorrow. Six in the morning. Go to the county library. Reserve computer time. Bring all the scratch paper. Bring the notebook of mistakes. Bring the full thirty yuan.

He blew out the lamp. The main room fell into darkness. Only the insects outside the window kept calling, once and then again.

The road had changed. The compiler had not started yet. But the first line of code had already been written.

He lay down and closed his eyes. His breathing was steady. His heartbeat fell into rhythm with the frogs calling in the distance.

Tomorrow. Six o’clock. Computer room. Reservation number. First machine. Power on. Log in. Type. Run.

If there was an error, then fix it. If the machine crashed, then restart. If the margin was not enough, then compress.

The pen had not stopped. The road was still being laid.

The night wind passed through the main room, stirring the scratch paper on the table. The pages turned and exposed the top line:

// TODO: Acquire the runtime environment.

A comment. Not the end. An instruction for the next step.

He turned over. The bandage on his left foot rubbed against the bedsheet. The pain was reclassified as a manageable parameter. He closed his eyes and silently recited the next nodes in sequence: August 12, admission notice arrives. September 1, registration. Forty-seven days in between. Computer room reservations. Part-time work to fill the gap. Code simulation.

The marks were still there. The margin was still being calculated.

Tomorrow. Six o’clock.