54 lines
955 B
TypeScript
54 lines
955 B
TypeScript
import { Lexer } from "./lexer.ts";
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const txt = await Deno.readTextFile("input.txt");
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const lexer = new Lexer(txt);
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function parseMulExpr(
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lexer: Lexer,
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){
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if (!lexer.match("mul(")) {
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return null;
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}
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const left = lexer.matchDigitN(1,3);
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if (!left) {
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return null;
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}
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if (!lexer.match(",")) {
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return null;
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}
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const right = lexer.matchDigitN(1,3);
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if (!right) {
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return null;
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}
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if (!lexer.match(")")) {
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return null;
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}
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return {
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type: "mul",
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left: parseInt(left),
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right: parseInt(right),
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};
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}
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const exprs: {
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type: string;
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left: number;
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right: number;
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}[] = [];
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while (lexer.pos < lexer.str.length) {
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const expr = parseMulExpr(lexer);
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if (expr) {
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exprs.push(expr);
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}
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else {
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lexer.next();
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}
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}
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let sum = 0;
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for (const expr of exprs) {
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sum += expr.left * expr.right;
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}
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console.log(sum); |