Solve Recursive Digit Sum from Hackerrank, CODEM5 from SPOJ, 1466 from URI and 990 from UVA

Author: AliOsm

Hackerrank/README.md

@@ -47,6 +47,7 @@
 - [Project Euler #10: Summation of primes](https://www.hackerrank.com/contests/projecteuler/challenges/euler010)
 - [Project Euler #11: Largest product in a grid](https://www.hackerrank.com/contests/projecteuler/challenges/euler011)
 - [Queues: A Tale of Two Stacks](https://www.hackerrank.com/challenges/ctci-queue-using-two-stacks)
+- [Recursive Digit Sum](https://www.hackerrank.com/challenges/recursive-digit-sum)
 - [Repeated String](https://www.hackerrank.com/challenges/repeated-string)
 - [Say "Hello, World!" With C++](https://www.hackerrank.com/challenges/cpp-hello-world)
 - [Sherlock and Anagrams](https://www.hackerrank.com/challenges/sherlock-and-anagrams)

Hackerrank/Recursive Digit Sum.cpp

@@ -0,0 +1,57 @@
+#include <iostream>
+#include <string>
+
+using namespace std;
+
+string n;
+int k, res;
+
+int toInt() {
+    int tmp = 0;
+    for(int i = 0; i < n.length(); ++i)
+        tmp += (n[i] - '0');
+    return tmp;
+}
+
+void stringSum() {
+    int tmp = 0;
+    for(int i = 0; i < n.length(); ++i)
+        tmp += (n[i] - '0');
+    
+    n = "";
+    while(tmp != 0) {
+        n += ((tmp % 10) + '0');
+        tmp /= 10;
+    }
+}
+
+void stringRec() {
+    stringSum();
+    if(n.length() == 1) return;
+    stringRec();
+}
+
+void intSum() {
+    int tmp = 0;
+    while(res != 0) {
+        tmp += (res % 10);
+        res /= 10;
+    }
+    res = tmp;
+}
+
+void intRec() {
+    intSum();
+    if(res < 10) return;
+    intRec();
+}
+
+int main() {
+    cin >> n >> k;
+    stringRec();
+    res = toInt() * k;
+    intRec();
+    cout << res << endl;
+    
+    return 0;
+}

SPOJ/CODEM5 - Problem5.cpp

@@ -0,0 +1,34 @@
+#include <stdio.h>
+#include <algorithm>
+
+using namespace std;
+
+int n, k, a[101];
+
+int rec(int i, int sum) {
+    if(sum == k)
+        return 0;
+        
+    if(i == n)
+        return 1e5;
+    
+    return min(rec(i + 1, sum + a[i]) + 1, rec(i + 1, sum));
+}
+
+int main() {
+    int t;
+    scanf("%d", &t);
+    while(t-- != 0) {
+        scanf("%d %d", &n, &k);
+        for(int i = 0; i < n; ++i)
+            scanf("%d", a + i);
+        
+        int res = rec(0, 0);
+        if(res >= 1e5)
+            puts("impossible");
+        else
+            printf("%d\n", res);
+    }
+    
+    return 0;
+}

SPOJ/README.md

@@ -6,6 +6,7 @@
 - [BGSHOOT - Shoot and kill](http://www.spoj.com/problems/BGSHOOT/)
 - [BSEARCH1 - Binary search](http://www.spoj.com/problems/BSEARCH1/)
 - [CODEIT02 - PICK UP DROP ESCAPE](http://www.spoj.com/problems/CODEIT02/)
+- [CODEM5 - Problem5](http://www.spoj.com/problems/CODEM5/)
 - [CPRIME - Prime Number Theorem](http://www.spoj.com/problems/CPRIME/)
 - [CRSCNTRY - Cross-country](http://www.spoj.com/problems/CRSCNTRY/)
 - [DCOWS - Dancing Cows](http://www.spoj.com/problems/DCOWS/)

URI/1466 - Level Order Tree Traversal.cpp

@@ -0,0 +1,96 @@
+#include <stdio.h>
+#include <memory.h>
+#include <queue>
+#include <vector>
+
+using namespace std;
+
+struct node {
+	static node *sentinel;
+
+	node *left, *right;
+	int value;
+
+	node() {
+		memset(this, 0, sizeof *this);
+	}
+
+	node(int value) {
+		left = right = sentinel;
+		this->value = value;
+	}
+};
+
+node *node::sentinel = new node;
+
+node * insert(node *cur, int &value) {
+	if(cur == node::sentinel) return new node(value);
+	if(cur->value > value) cur->left = insert(cur->left, value);
+	if(cur->value < value) cur->right = insert(cur->right, value);
+	return cur;
+}
+
+void free_bst(node *cur) {
+	if(cur == node::sentinel) return;
+	free_bst(cur->left);
+	free_bst(cur->right);
+	delete cur;
+}
+
+int n, tmp;
+queue<node*> qu;
+vector<int> bfs_res;
+
+void BFS(node *cur) {
+	while(!qu.empty()) qu.pop();
+	qu.push(cur);
+
+	int size;
+	node *fr;
+	while(!qu.empty()) {
+		size = qu.size();
+
+		while(size-- != 0) {
+			fr = qu.front();
+			qu.pop();
+
+			bfs_res.push_back(fr->value);
+
+			if(fr->left != node::sentinel)
+				qu.push(fr->left);
+
+			if(fr->right!= node::sentinel)
+				qu.push(fr->right);
+		}
+	}
+}
+
+int main() {
+	node *root;
+
+	int t;
+	scanf("%d", &t);
+	for(int cnt = 1; t-- != 0; ++cnt) {
+		bfs_res.clear();
+		root = NULL;
+
+		scanf("%d", &n);
+		for(int i = 0; i < n; ++i) {
+			scanf("%d", &tmp);
+			if(root == NULL)
+				root = new node(tmp);
+			else
+				insert(root, tmp);
+		}
+
+		printf("Case %d:\n", cnt);
+		BFS(root);
+		for(int i = 0; i < (int)bfs_res.size(); ++i)
+			printf("%s%d", (i != 0 ? " " : ""), bfs_res[i]);
+		puts("\n");
+		free_bst(root);
+	}
+
+	return 0;
+}
+

URI/README.md

@@ -69,6 +69,7 @@
 - [1424 - Easy Problem from Rujia Liu?](https://www.urionlinejudge.com.br/judge/en/problems/view/1424)
 - [1430 - Jingle Composing](https://www.urionlinejudge.com.br/judge/en/problems/view/1430)
 - [1451 - Broken Keyboard](https://www.urionlinejudge.com.br/judge/en/problems/view/1451)
+- [1466 - Level Order Tree Traversal](https://www.urionlinejudge.com.br/judge/en/problems/view/1466)
 - [1467 - Zero or One](https://www.urionlinejudge.com.br/judge/en/problems/view/1467)
 - [1469 - Boss](https://www.urionlinejudge.com.br/judge/en/problems/view/1469)
 - [1548 - Canteen Queue](https://www.urionlinejudge.com.br/judge/en/problems/view/1548)

UVA/990 - Diving for Gold.cpp

@@ -0,0 +1,68 @@
+#include <stdio.h>
+#include <memory.h>
+#include <vector>
+#include <algorithm>
+
+using namespace std;
+
+int t, w, n, dp[1001][31];
+pair<int, int> treasures[31];
+vector<int> sol;
+
+int rec(int time, int index) {
+	if(time < 0)
+		return -1e5;
+
+	if(index == n)
+		return 0;
+
+	int &ret = dp[time][index];
+	if(ret != -1) return ret;
+	ret = 0;
+
+	int r1, r2;
+
+	r1 = rec(time - (3 * w * treasures[index].first), index + 1) + treasures[index].second;
+	r2 = rec(time, index + 1);
+
+	return ret = max(r1, r2);
+}
+
+void build_path(int time, int index) {
+	if(time < 0)
+		return;
+
+	if(index == n)
+		return;
+
+	if(rec(time, index) == rec(time - (3 * w * treasures[index].first), index + 1) + treasures[index].second) {
+		sol.push_back(index);
+		build_path(time - (3 * w * treasures[index].first), index + 1);
+	} else {
+		build_path(time, index + 1);
+	}
+}
+
+int main() {
+	bool blankline = false;
+	while(scanf("%d %d", &t, &w) != EOF) {
+		if(blankline) puts("");
+		scanf("%d", &n);
+		for(int i = 0; i < n; ++i)
+			scanf("%d %d", &treasures[i].first, &treasures[i].second);
+
+		memset(dp, -1, sizeof dp);
+		printf("%d\n", rec(t, 0));
+
+		sol.clear();
+		build_path(t, 0);
+
+		printf("%d\n", (int)sol.size());
+		for(int i = 0; i < (int)sol.size(); ++i)
+			printf("%d %d\n", treasures[sol[i]].first, treasures[sol[i]].second);
+		blankline = true;
+	}
+
+	return 0;
+}
+

UVA/README.md

@@ -38,6 +38,7 @@
 - [836 - Largest Submatrix](https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=777)
 - [900 - Brick Wall Patterns](https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=841)
 - [929 - Number Maze](https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=24&page=show_problem&problem=870)
+- [990 - Diving for Gold](https://uva.onlinejudge.org/index.php?option=onlinejudge&page=show_problem&problem=931)
 - [1121 - Subsequence](https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=3562)
 - [1124 - Celebrity jeopardy](https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=3565)
 - [1148 - The mysterious X network](https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=3589)