34 lines
999 B
TypeScript
34 lines
999 B
TypeScript
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const fs = require('fs');
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const input = fs.readFileSync(__dirname + '/input.txt', 'utf8');
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const equations: Array<string> = input.split("\n");
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let sum = 0;
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const operators = [(a: number, b: number) => a * b, (a: number, b: number) => a + b, /** Part 2 */ (a: number, b: number) => parseInt(''+a+b)];
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function recurseSum(carry: number, remaining: Array<number>, target: number, sum: string = ''): boolean {
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if (!remaining.length) {
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return target === carry;
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}
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const nextNum = remaining[0];
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for (let o of operators) {
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const newResult = recurseSum(o(carry, nextNum), remaining.slice(1), target);
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if (newResult) {
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return newResult;
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}
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};
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return false;
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}
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equations.forEach((eq) => {
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const [testStr, numStr] = eq.split(':');
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const test = parseInt(testStr);
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const nums = numStr.trim().split(' ').map((n) => parseInt(n));
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if (recurseSum(nums[0], nums.slice(1), test)) {
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sum += test;
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}
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});
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console.log(sum);
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