Lab4 Iteration

Author: vladimirvikulin

.eslintrc.json

@@ -18,7 +18,7 @@
     ],
     "linebreak-style": [
       "error",
-      "unix"
+      "windows"
     ],
     "quotes": [
       "error",

Exercises/1-for.js

@@ -1,9 +1,11 @@
 'use strict';
 
 const sum = (...args) => {
-  // Use for loop and accumulator variable
-  // to calculate sum of all given arguments
-  // For example sum(1, 2, 3) should return 6
+  let sum = 0;
+  for (let i = 0; i < args.length; i++) {
+    sum += args[i];
+  }
+  return sum;
 };
-
+console.log(sum(1, 2, 3));
 module.exports = { sum };

Exercises/2-for-of.js

@@ -1,9 +1,11 @@
 'use strict';
 
 const sum = (...args) => {
-  // Use for..of loop and accumulator variable
-  // to calculate sum of all given arguments
-  // For example sum(1, 2, 3) should return 6
+  let sum = 0;
+  for (const element of args) {
+    sum += element;
+  }
+  return sum;
 };
-
+console.log(sum());
 module.exports = { sum };

Exercises/3-while.js

@@ -1,9 +1,12 @@
 'use strict';
 
 const sum = (...args) => {
-  // Use while loop and accumulator variable
-  // to calculate sum of all given arguments
-  // For example sum(1, 2, 3) should return 6
+  let sum = 0;
+  let i = 0;
+  while (i < args.length) {
+    sum += args[i++];
+  }
+  return sum;
 };
-
+console.log(sum(1, 3));
 module.exports = { sum };

Exercises/4-do-while.js

@@ -1,9 +1,13 @@
 'use strict';
 
 const sum = (...args) => {
-  // Use do..while loop and accumulator variable
-  // to calculate sum of all given arguments
-  // For example sum(1, 2, 3) should return 6
+  if (args.length === 0) return 0;
+  let sum = 0;
+  let i = 0;
+  do {
+    sum += args[i++];
+  } while (i < args.length);
+  return sum;
 };
-
+console.log(sum(1, 2, 3, 6));
 module.exports = { sum };

Exercises/5-reduce.js

@@ -1,8 +1,5 @@
 'use strict';
 
-const sum = (...args) => 0;
-// Use Array.prototype.reduce method
-// to calculate sum of all given arguments
-// For example sum(1, 2, 3) should return 6
-
+const sum = (...args) => args.reduce((prev, cur) => prev + cur, 0);
+console.log(sum(0, 3, -5));
 module.exports = { sum };

Exercises/6-matrix.js

@@ -1,9 +1,16 @@
 'use strict';
 
-const max = matrix => {
-  // Use nested for loop to find max value in 2d matrix
-  // For example max([[1, 2, 3], [4, 5, 6], [7, 8, 9]])
-  // should return 9
+const max = (matrix) => {
+  let max = matrix[0][0];
+  for (let i = 0; i < matrix.length; i++) {
+    const row = matrix[i];
+    for (let j = 0; j < row.length; j++) {
+      if (max < row[j])
+        max = row[j];
+    }
+  }
+  return max;
 };
-
+const m = max([[1, 2, 3], [4, 5, 6], [7, 8, 9]]);
+console.log(m);
 module.exports = { max };

Exercises/7-ages.js

@@ -1,19 +1,17 @@
 'use strict';
 
-const ages = persons => {
-  // Use for..in to calculate age for each person
-  // For example ages({
-  //   lenin: { born: 1870, died: 1924 },
-  //   mao: { born: 1893, died: 1976 },
-  //   gandhi: { born: 1869, died: 1948 },
-  //   hirohito: { born: 1901, died: 1989 },
-  // })
-  // should return {
-  //   lenin: 54,
-  //   mao: 83,
-  //   gandhi: 79,
-  //   hirohito: 88,
-  // }
+const ages = (persons) => {
+  const ages = {};
+  for (const personsKey in persons) {
+    ages[personsKey] = persons[personsKey].died - persons[personsKey].born;
+  }
+  return ages;
 };
-
+const persons = {
+  lenin: { born: 1870, died: 1924 },
+  mao: { born: 1893, died: 1976 },
+  gandhi: { born: 1869, died: 1948 },
+  hirohito: { born: 1901, died: 1989 },
+};
+console.log(ages(persons));
 module.exports = { ages };