Day 1

1/1/main.go

@@ -0,0 +1,41 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"log"
+	"os"
+	"strconv"
+)
+
+func main() {
+	file, err := os.Open("../input.txt")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer file.Close()
+
+	numbers := []int{}
+
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		n, err := strconv.Atoi(scanner.Text())
+		if err != nil {
+			log.Fatal(err)
+		}
+		numbers = append(numbers, n)
+	}
+	if err := scanner.Err(); err != nil {
+		log.Fatal(err)
+	}
+
+	for _, i := range numbers {
+		for _, j := range numbers {
+			if i+j == 2020 {
+				fmt.Println(i * j)
+				return
+			}
+		}
+	}
+
+}

1/2/main.go

@@ -0,0 +1,43 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"log"
+	"os"
+	"strconv"
+)
+
+func main() {
+	file, err := os.Open("../input.txt")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer file.Close()
+
+	numbers := []int{}
+
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		n, err := strconv.Atoi(scanner.Text())
+		if err != nil {
+			log.Fatal(err)
+		}
+		numbers = append(numbers, n)
+	}
+	if err := scanner.Err(); err != nil {
+		log.Fatal(err)
+	}
+
+	for _, i := range numbers {
+		for _, j := range numbers {
+			for _, k := range numbers {
+				if i+j+k == 2020 {
+					fmt.Println(i * j * k)
+					return
+				}
+			}
+		}
+	}
+
+}

1/input.txt

@@ -0,0 +1,200 @@
+1583
+1295
+1747
+1628
+1756
+1992
+1984
+1990
+2006
+1626
+1292
+1561
+1697
+1249
+2001
+1822
+1715
+1951
+1600
+1615
+1769
+1825
+1335
+1987
+1745
+1660
+1952
+1437
+1348
+1968
+615
+1847
+476
+1346
+1357
+1838
+1955
+1750
+1831
+2003
+1730
+1696
+1257
+1581
+866
+1765
+1691
+1995
+1977
+1988
+1713
+1599
+1300
+1892
+1550
+2002
+1694
+1930
+1998
+1564
+1704
+1398
+864
+1480
+1578
+1946
+1850
+1964
+1914
+1860
+1979
+1857
+1969
+1675
+1967
+2009
+1950
+1834
+783
+1935
+1963
+1659
+1314
+1647
+1671
+1706
+1734
+1965
+1666
+316
+1657
+1663
+1373
+1719
+1778
+1559
+1869
+1958
+1986
+1845
+1643
+1783
+1670
+1445
+1758
+2008
+1680
+1251
+1982
+1420
+1621
+1997
+1785
+1994
+1376
+1944
+1771
+1844
+96
+467
+1954
+903
+1368
+1305
+1589
+1970
+1980
+1521
+1775
+1629
+1796
+1985
+1957
+1669
+1637
+1606
+1766
+1972
+1956
+1685
+1235
+58
+1996
+1959
+1788
+1273
+1378
+1233
+1470
+1584
+1741
+1327
+1763
+1989
+1665
+1667
+1975
+1862
+1791
+1229
+1873
+1761
+1754
+1882
+1642
+1971
+1777
+1580
+1648
+1678
+1266
+1645
+502
+1717
+1723
+1244
+1370
+1898
+1755
+1708
+1983
+1901
+844
+1239
+1290
+1879
+1656
+1966
+1929
+1993
+1743
+1909
+1451
+2000
+1978
+1938
+1707
+1337
+1362
+1263