8 files changed, 99 insertions, 3 deletions
diff --git a/03/src/.main.rs.swo b/03/src/.main.rs.swo
deleted file mode 100644
index fead7a5..0000000
--- a/03/src/.main.rs.swo
+++ /dev/null
Binary files differdiff --git a/06/tests/main.rs b/06/tests/main.rs
index ad291d8..829f000 100644
--- a/06/tests/main.rs
+++ b/06/tests/main.rs
@@ -5,12 +5,12 @@ use std::process::Command;
 
 #[test]
 fn personal_input() -> Result<(), Box<dyn std::error::Error>> {
-  let mut command = Command::cargo_bin("advent_05")?;
+  let mut command = Command::cargo_bin("advent_06")?;
 
   command.arg("input");
   command.assert().success().stdout(
-      "4655\n\
-      20500\n");
+      "386536\n\
+      1732821262171\n");
 
   Ok(())
 }
diff --git a/07/Cargo.toml b/07/Cargo.toml
new file mode 100644
index 0000000..48a5aff
--- /dev/null
+++ b/07/Cargo.toml
@@ -0,0 +1,11 @@
+[package]
+name = "advent_07"
+version = "0.1.0"
+authors = ["Irene Knapp <ireneista@gmail.com>"]
+edition = "2018"
+
+[dependencies]
+advent_lib = { path = "../lib" }
+
+[dev-dependencies]
+assert_cmd = "0.10"
diff --git a/07/input b/07/input
new file mode 100644
index 0000000..80aca77
--- /dev/null
+++ b/07/input
@@ -0,0 +1 @@
+1101,1,29,67,1102,0,1,65,1008,65,35,66,1005,66,28,1,67,65,20,4,0,1001,65,1,65,1106,0,8,99,35,67,101,99,105,32,110,39,101,115,116,32,112,97,115,32,117,110,101,32,105,110,116,99,111,100,101,32,112,114,111,103,114,97,109,10,209,573,1277,704,518,276,196,62,1226,170,58,1450,101,65,99,435,986,1437,1570,35,354,247,110,105,139,1209,23,1074,339,69,483,21,33,323,1348,111,2,270,1239,316,529,1680,1056,1960,257,1009,1073,59,425,1181,198,31,299,771,53,817,728,931,72,517,39,279,304,401,1271,533,1551,133,297,162,902,370,985,643,1217,78,16,380,223,177,600,349,12,776,26,1738,526,85,1542,111,844,93,595,1545,873,836,422,180,1187,329,231,1521,54,162,212,471,1329,156,1299,160,541,676,67,200,22,24,76,242,178,1093,1173,818,1380,284,335,642,1047,112,271,541,927,52,983,238,116,135,871,400,436,1094,684,249,263,303,24,437,813,32,45,19,620,57,866,44,68,277,1112,110,77,1481,437,302,678,541,904,322,13,186,1474,836,43,1020,201,1586,1169,1149,470,535,55,879,133,1229,106,989,1023,256,103,56,401,667,557,98,288,694,286,237,1661,933,1063,20,227,80,815,289,1414,234,517,227,616,829,191,1211,92,591,279,22,139,67,214,60,145,468,10,521,807,1243,76,163,190,122,804,88,383,319,1127,399,376,423,304,126,10,297,377,1103,691,139,70,519,16,15,43,397,468,1183,90,28,1262,151,1448,62,64,1072,386,1330,1313,12,100,657,28,55,612,337,1865,704,263,565,249,564,565,1218,40,1146,150,718,1253,228,120,713,925,159,36,1087,1023,1490,316,540,1124,1127,781,417,656,0,174,1006,529,389,86,90,78,403,1500,253,35,655,650,933,815,108,168,321,345,147,251,258,25,173,243,740,48,476,1507,634,425,738,160,1415,395,448,156,636,1967,516,316,628,810,817,26,20,753,22,1133,352,204,211,47,22,874,43,12,18,1015,779,108,579,251,1398,33,1507,93,274,904,221,1062,868,3,363,42,14,435,62,1508,540,64,267,1690,418,205,502,152,142,414,178,50,344,780,81,635,128,355,239,1708,1814,29,251,624,22,38,789,948,186,529,895,76,150,416,502,975,1216,456,862,522,1149,131,10,121,1353,313,568,595,6,318,633,331,1652,656,214,21,35,289,80,860,229,244,1188,350,594,424,235,327,6,1083,40,134,839,279,172,1452,197,47,2,73,607,238,1151,844,533,110,1207,125,129,16,1000,965,236,228,497,589,111,1245,453,179,956,116,212,47,497,380,574,355,799,209,384,47,449,688,312,748,1531,1092,23,1001,69,155,924,1352,163,1561,743,609,1261,1231,32,1,739,513,300,370,36,568,89,487,201,11,146,274,163,1029,829,469,299,118,732,769,120,1093,776,610,1944,90,67,494,831,88,227,1257,344,662,401,310,664,56,94,183,935,179,643,4,1083,567,1525,208,204,899,123,36,438,1171,265,1406,177,202,1398,631,444,385,589,29,124,96,237,374,793,794,502,665,287,575,113,305,157,465,376,66,662,77,595,75,141,243,254,30,5,622,140,443,566,360,192,1531,1113,1299,598,147,469,732,1565,409,1380,550,173,232,361,131,99,37,547,132,1779,193,228,664,553,568,389,1069,58,71,610,738,624,261,491,158,105,416,131,198,35,823,9,313,6,429,1492,290,313,272,281,427,280,661,141,54,383,3,130,43,418,2,1040,1051,1006,38,151,1325,1357,117,1473,175,201,613,1458,1218,588,169,228,565,901,420,42,117,110,442,9,99,1685,979,84,35,129,248,1,21,360,123,203,1320,1200,209,510,362,106,148,313,292,63,842,93,88,134,720,565,156,118,983,119,1451,757,736,445,466,226,265,573,612,652,170,225,32,1049,1332,366,1375,692,270,388,321,1153,909,1266,93,5,495,377,212,429,90,199,278,631,693,63,816,395,281,315,0,737,575,121,865,1,485,262,49,804,518,109,600,358,221,14,370,450,947,448,67,576,22,1266,226,100,10,607,620,295,568,316,51,687,199,1478,45,489,1878,1035,298,219,363,85,664,1290,492,70,644,78,163,100,102,465,732,439,93,25,847,297,172,361,393,304,461,583,122,121,762,58,112,85,142,48,193,1617,386,685,1054,584,488,394,665,277,263,596,290,1231,171,1394,9,1218,77,54,487,182,528,695,662,413,345,51,690,1702,203,1500,461,1755,190,371,1122,1614,324,238,569,1482,15,711,1332,700,437,242,174,642,660,987,1232,121,620,17,389,22,105,847,36,251,285,1238,162,1227,1473,411,66,258,377,1135,438,117,664,281,1070,301,132,256,498,172,194,103,662,606,342,340,1501,802,549,380,58,179,361
diff --git a/07/src/main.rs b/07/src/main.rs
new file mode 100644
index 0000000..a22129a
--- /dev/null
+++ b/07/src/main.rs
@@ -0,0 +1,58 @@
+use advent_lib::prelude::*;
+
+
+fn main() -> Result<()> {
+  let mut args = std::env::args();
+  if args.len() != 2 {
+    eprintln!("Usage: advent input");
+  }
+  let _ = args.next();
+  let filename = args.next().unwrap();
+
+  let input = advent_lib::read_lines_file(&filename)?;
+
+  let mut start_positions = Vec::new();
+  for word in input[0].split(',') {
+    let position = word.parse::<i64>()?;
+    start_positions.push(position);
+  }
+  start_positions.sort();
+
+  {
+    let median = start_positions[start_positions.len() / 2];
+    let mut cost = 0;
+    for position in &start_positions {
+      cost += (median - position).abs();
+    }
+    println!("{}", cost);
+  }
+
+  {
+    let min = start_positions[0];
+    let max = start_positions[start_positions.len() - 1];
+    let mut best_cost = None;
+
+    for destination in min .. max + 1 {
+      let mut cost = 0;
+      for position in &start_positions {
+        let distance = (destination - position).abs();
+        cost += distance * (distance + 1) / 2;
+      }
+
+      match best_cost {
+        None => {
+          best_cost = Some(cost);
+        },
+        Some(old_best) => {
+          if cost < old_best {
+            best_cost = Some(cost);
+          }
+        },
+      }
+    }
+
+    println!("{}", best_cost.unwrap());
+  }
+
+  Ok(())
+}
diff --git a/07/tests/main.rs b/07/tests/main.rs
new file mode 100644
index 0000000..e9b1eb4
--- /dev/null
+++ b/07/tests/main.rs
@@ -0,0 +1,17 @@
+use assert_cmd::prelude::*;
+//use predicates::prelude::*;
+use std::process::Command;
+
+
+#[test]
+fn personal_input() -> Result<(), Box<dyn std::error::Error>> {
+  let mut command = Command::cargo_bin("advent_07")?;
+
+  command.arg("input");
+  command.assert().success().stdout(
+      "343441\n\
+      98925151\n");
+
+  Ok(())
+}
+
diff --git a/Cargo.lock b/Cargo.lock
index 8f6d6d1..234cf5d 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -49,6 +49,14 @@ dependencies = [
 ]
 
 [[package]]
+name = "advent_07"
+version = "0.1.0"
+dependencies = [
+ "advent_lib",
+ "assert_cmd",
+]
+
+[[package]]
 name = "advent_lib"
 version = "0.1.0"
 dependencies = [
diff --git a/Cargo.toml b/Cargo.toml
index 6a830cc..48403e3 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -7,4 +7,5 @@ members = [
   "04",
   "05",
   "06",
+  "07",
 ]