POJ---To and Fro;Speed Limit;Error Correction;Lotto;Series Determination;Trees;Lab杯;Jugs;史上最难的问题;Parencodings;To the Max;Web Nav

本文链接：https://blog.youkuaiyun.com/yiming910/article/details/4059044

本文解析了多个编程挑战题目，包括算法实现、数据处理和逻辑运算等。通过具体代码示例展示了如何解决这些问题，覆盖了从输入处理到输出展示的全过程。

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To and Fro：

/** * 2039 To and Fro */ #include <iostream> #include <string> using namespace std; void output(const string& str, int num) { for (int i = 0; i < num; i++) { int end = num * 2 - 1 - i; int begin = i; for (int j = 0; j < str.length() / num / 2 + 1; j++) { int start = begin + 2 * num * j; if (start < str.length()) { cout << str[start]; } int eof = end + 2 * num * j; if (eof < str.length()) { cout << str[eof]; } } } cout<< endl; } int main() { int num = 0; string str; cin >> num; while (num != 0) { cin >> str; output(str, num); cin >> num; } return 0; }

Speed Limit:

import java.util.Scanner; public class Main { public static void main(String args[]) { Scanner s = new Scanner(System.in); int num = s.nextInt(); int a; int b; int before = 0; int sum = 0; while (num != -1) { for (int i = 0; i < num; i++) { a = s.nextInt(); b = s.nextInt(); sum += a * (b - before); before = b; } System.out.println(sum + " miles"); num = s.nextInt(); before = 0; sum = 0; } } }

Error Correction:

import java.util.Scanner; public class Main { public static void main(String args[]) { Scanner s = new Scanner(System.in); int num = s.nextInt(); while (num != 0) { int sum = num * num; int index = -1; boolean isOK = true; int[] a = new int[sum]; for (int i = 0; i < num; i++) { int all = 0; for (int j = 0; j < num; j++) { a[i * num + j] = s.nextInt(); all += a[i * num + j]; } if (all % 2 != 0) { if (index != -1) { isOK = false; } else { index = i; } } } if (!isOK) { System.out.println("Corrupt"); } else { int c = getColoum(a, num);// -1代表两列以上不对，-2代表都对，其他 if (index != -1) { if (c != -1 && c != -2) { System.out.println("Change bit (" + (index + 1) + "," + (c + 1) + ")"); } else { System.out.println("Corrupt"); } } else { if (c == -2) { System.out.println("OK"); } else { System.out.println("Corrupt"); } } } num = s.nextInt(); } } public static int getColoum(int[] a, int num) { boolean is2 = true; int index = -1; for (int i = 0; i < num; i++) { int all = 0; for (int j = 0; j < num; j++) { all += a[i + j * num]; } if (all % 2 != 0) { is2 = false; if (index == -1) { index = i; } else { return -1; } } } if (is2) { return -2; } else { return index; } } }

Lotto:

#include <cstdio> int store[6], num, in[15]; void output() { printf("%d %d %d %d %d %d/n", store[0], store[1], store[2], store[3], store[4], store[5]); } void dfs(int from, int now) { int i; if(now == 6) { output(); return; } for(i = from; i <= num - 6 + now; i++) { store[now] = in[i]; dfs(i + 1, now + 1); } } int main() { int start = 0; int i; while(scanf("%d",&num) == 1 && num) { if(start) printf("/n"); start = 1; for(i = 0; i < num; i++) scanf("%d", &in[i]); dfs(0, 0); } return 0; }

Series Determination:

import java.util.Scanner; public class Main { public static int f[] = new int[10]; public static int A, B, C; public static void main(String[] args) { Scanner s = new Scanner(System.in); for (int i = 0; i < 100; i++) { f[0] = s.nextInt(); f[1] = s.nextInt(); f[2] = s.nextInt(); init(); count(); System.out.println(f[3] + " " + f[4] + " " + f[5]); } } private static void count() { f[3] = A * 3 * 3 + B * 3 + C; f[4] = A * 4 * 4 + B * 4 + C; f[5] = A * 5 * 5 + B * 5 + C; } private static void init() { C = f[0]; A = (f[2] - 2 * f[1] + f[0]) / 2; B = (int) (2 * f[1] - 1.5 * f[0] - 0.5 * f[2]); } }

Trees:

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner s = new Scanner(System.in); int length = s.nextInt(); int sn = s.nextInt(); while (true) { if (length == 0 && sn == 0) { break; } int a[] = new int[sn]; length += 1; for (int i = 0; i < sn; i++) { int start = s.nextInt(); int end = s.nextInt(); a[i] = end - start + 1; length -= a[i]; } System.out.println(length); length = s.nextInt(); sn = s.nextInt(); } } }

Lab杯:

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner s = new Scanner(System.in); int num = s.nextInt(); int[][] n = new int[num][num]; int[] y = new int[num]; for (int i = 0; i < num; i++) { y[i] = 0; for (int j = 0; j < num; j++) { n[i][j] = s.nextInt(); } } for (int i = 0; i < num; i++) { for (int j = 0; j < i; j++) { if (n[i][j] == 3) { y[i]++; } else { y[j]++; } } } int max = y[0]; int index = 1; for (int i = 0; i < num; i++) { if (y[i] > max) { index = i + 1; max = y[i]; } } System.out.println(index); } }

Jugs:

#include <string.h> #include <iostream> using namespace std; int min(int a, int b) { return a < b ? a : b; } struct { int a, b, last, operation; }queue[65535]; int front, rear; bool isRepeat[1001][1001]; void outPut(int i) { if(i == 0) return; outPut(queue[i].last); switch(queue[i].operation) { case 1 : cout << "fill A" << endl; break; case 2 : cout << "fill B" << endl; break; case 3 : cout << "empty A" << endl; break; case 4 : cout << "empty B" << endl; break; case 5 : cout << "pour A B" << endl; break; case 6 : cout << "pour B A" << endl; break; } } int main() { int A, B, N; while(cin >> A >> B >> N) { memset(isRepeat, 0, sizeof(isRepeat)); front = -1, rear = 0; queue[0].a = queue[0].b = 0; queue[0].last = queue[0].operation = 0; while(front < rear) { front++; int a = queue[front].a; int b = queue[front].b; if(b == N) { outPut(front); cout << "success" << endl; break; } //fill A if(a != A) { rear++; queue[rear].a = A; queue[rear].b = b; queue[rear].last = front; queue[rear].operation = 1; if(isRepeat[queue[rear].a][queue[rear].b]) rear--; else isRepeat[queue[rear].a][queue[rear].b] = true; } //fill B if(b != B) { rear++; queue[rear].a = a; queue[rear].b = B; queue[rear].last = front; queue[rear].operation = 2; if(isRepeat[queue[rear].a][queue[rear].b]) rear--; else isRepeat[queue[rear].a][queue[rear].b] = true; } //empty A if(a != 0) { rear++; queue[rear].a = 0; queue[rear].b = b; queue[rear].last = front; queue[rear].operation = 3; if(isRepeat[queue[rear].a][queue[rear].b]) rear--; else isRepeat[queue[rear].a][queue[rear].b] = true; } //empty B if(b != 0) { rear++; queue[rear].a = a; queue[rear].b = 0; queue[rear].last = front; queue[rear].operation = 4; if(isRepeat[queue[rear].a][queue[rear].b]) rear--; else isRepeat[queue[rear].a][queue[rear].b] = true; } //pour A to B rear++; queue[rear].a = a - min(a, B - b); queue[rear].b = b + min(a, B - b); queue[rear].last = front; queue[rear].operation = 5; if(isRepeat[queue[rear].a][queue[rear].b]) rear--; else isRepeat[queue[rear].a][queue[rear].b] = true; //pour B to A rear++; queue[rear].a = a + min(b, A - a); queue[rear].b = b - min(b, A - a); queue[rear].last = front; queue[rear].operation = 6; if(isRepeat[queue[rear].a][queue[rear].b]) rear--; else isRepeat[queue[rear].a][queue[rear].b] = true; } } return 0; }

史上最难的问题:

import java.util.HashMap; import java.util.Map; import java.util.Scanner; public class Main { private static Map<Character, Character> m = new HashMap<Character, Character>( 26); static { m.put('A', 'V'); m.put('B', 'W'); m.put('C', 'X'); m.put('D', 'Y'); m.put('E', 'Z'); m.put('F', 'A'); m.put('G', 'B'); m.put('H', 'C'); m.put('I', 'D'); m.put('J', 'E'); m.put('K', 'F'); m.put('L', 'G'); m.put('M', 'H'); m.put('N', 'I'); m.put('O', 'J'); m.put('P', 'K'); m.put('Q', 'L'); m.put('R', 'M'); m.put('S', 'N'); m.put('T', 'O'); m.put('U', 'P'); m.put('V', 'Q'); m.put('W', 'R'); m.put('X', 'S'); m.put('Y', 'T'); m.put('Z', 'U'); } public static void main(String[] args) { Scanner s = new Scanner(System.in); for (int i = 0; i < 100; i++) { String n = s.nextLine(); if (n.equals("ENDOFINPUT")) { return; } if (n.equals("START")) { StringBuffer b = new StringBuffer(); String data = s.nextLine(); for (char c : data.toCharArray()) { if (c >= 'A' && c <= 'Z') { b.append(m.get(c)); } else { b.append(c); } } s.nextLine(); System.out.println(b.toString()); } } } }

Parencodings:

import java.util.Scanner; public class Main2 { public static void main(String[] args) { Scanner cin = new Scanner(System.in); int num = cin.nextInt(); for (int i = 0; i < num; i++) { int n = cin.nextInt(); int[] a = new int[n]; int[] b = new int[n]; for (int j = 0; j < n; j++) { if (j == 0) { a[j] = cin.nextInt(); b[j] = a[j]; continue; } a[j] = cin.nextInt(); b[j] = a[j] - a[j - 1]; } for (int k = 0; k < n; k++) { if (k == 0) { System.out.print(1 + " "); b[k]--; continue; } for (int m = k; m >= 0; m--) { if (m == 0) { System.out.print((k + 1) + " "); continue; } if (b[m] > 0) { b[m]--; System.out.print((k - m + 1) + " "); break; } } } System.out.println(); } } }

To the Max:

import java.util.Scanner; public class Main { public static void main(String[] args) { int c, res = 0, k; int[] s = new int[101]; int[] a = new int[100]; int[][] d = new int[100][100]; Scanner cin = new Scanner(System.in); c = cin.nextInt(); if (c == 1) { System.out.println(cin.nextInt()); return; } for (int i = 0; i < c; i++) { for (int j = 0; j < c; j++) { d[i][j] = cin.nextInt(); } } for (int i = 0; i < c; i++) { for (int j = (i + 1); j < c; j++) { s[0] = 0; for (int l = 0; l < 100; l++) { a[l] = 0; s[l] = 0; } for (k = 0; k < c; k++) { for (int m = i; m <= j; m++) a[k] += d[m][k]; if (s[k] >= 0) s[k + 1] = s[k] + a[k]; else s[k + 1] = a[k]; } for (int i1 = 0; i1 <= k; i1++) { if (res < s[i1]) res = s[i1]; } } } System.out.println(res); } }

Web Navigation:

import java.util.Scanner; import java.util.Stack; import java.util.StringTokenizer; public class Main { public static void main(String args[]) { Stack<String> back = new Stack<String>(); Stack<String> forward = new Stack<String>(); String current = "http://www.acm.org/"; Scanner s = new Scanner(System.in); String command = ""; while (!((command = s.nextLine()).startsWith("QUIT"))) { if (command.startsWith("VISIT")) { String url = getUrl(command); back.push(current); current = url; forward.clear(); System.out.println(current); } else if (command.startsWith("BACK")) { if (back.isEmpty()) { System.out.println("Ignored"); continue; } String poll = back.pop(); forward.push(current); current = poll; System.out.println(current); } else if (command.startsWith("FORWARD")) { if (forward.isEmpty()) { System.out.println("Ignored"); continue; } String poll = forward.pop(); back.push(current); current = poll; System.out.println(current); } } } public static String getUrl(String str) { StringTokenizer nizer = new StringTokenizer(str, " "); nizer.nextToken(); return nizer.nextToken(); } }

求高精度幂:

import java.util.*; import java.math.*; public class Main { public static void main(String args[]) { int i, tag; Scanner cin = new Scanner(System.in); while (cin.hasNextBigDecimal()) { BigDecimal a = cin.nextBigDecimal(); int b = cin.nextInt(); tag = 0; a = a.pow(b); String temp = a.toPlainString(); for (i = 0; i < temp.length() - 1; i++) if (temp.charAt(i) == '.') { tag = 1; break; } if (tag == 1) { for (i = temp.length() - 1; i >= 0;) { if (temp.charAt(i) == '0') i--; else break; if (temp.charAt(i) == '.') { i--; break; } } } if (temp.charAt(0) != '0') System.out.println(temp.substring(0, i + 1)); else System.out.println(temp.substring(1, i + 1)); } } }

487-3279:

import java.util.ArrayList; import java.util.Collections; import java.util.HashMap; import java.util.HashSet; import java.util.List; import java.util.Map; import java.util.Scanner; public class Main { private static Map<String, Result> rl = new HashMap<String, Result>(15); private static Map<Character, Integer> map = new HashMap<Character, Integer>(); static { map.put('A', 2); map.put('B', 2); map.put('C', 2); map.put('D', 3); map.put('E', 3); map.put('F', 3); map.put('G', 4); map.put('H', 4); map.put('I', 4); map.put('J', 5); map.put('K', 5); map.put('L', 5); map.put('M', 6); map.put('N', 6); map.put('O', 6); map.put('P', 7); map.put('R', 7); map.put('S', 7); map.put('T', 8); map.put('U', 8); map.put('V', 8); map.put('W', 9); map.put('X', 9); map.put('Y', 9); } public static void main(String[] args) { Scanner cin = new Scanner(System.in); int num = cin.nextInt(); HashSet<String> r2 = new HashSet<String>(num); cin.nextLine(); for (int i = 0; i < num; i++) { String nextLine = cin.nextLine(); String ns = NS(nextLine); if (!r2.contains(ns)) { r2.add(ns); } else { if (rl.containsKey(ns)) { Result result = rl.get(ns); int num2 = result.getNum(); num2++; result.setNum(num2); } else { rl.put(ns, new Result(2, ns)); } } } if (rl.size() == 0) { System.out.println("No duplicates."); return; } List<Result> sortList = new ArrayList<Result>(); sortList.addAll(rl.values()); Collections.sort(sortList); for (Result r : sortList) { System.out.println(r.getNumber() + " " + r.getNum()); } } public static String NS(String str) { String number = ""; int index = 0; for (char c : str.toCharArray()) { if (!Character.isDigit(c)) { if (c == '-') { continue; } Integer a = map.get(c); if (a != null) { int b = a.intValue(); index++; number += b; } else { return null; } } else { index++; number += c; } if (index == 3) { number += "-"; } } return number; } private static class Result implements Comparable<Result> { public boolean equals(Object o) { if (o != null && o instanceof Result) { if (this.number.equals(((Result) o).getNumber())) { return true; } } return false; } private int num; private String number; public Result() { } public Result(int num, String number) { this.num = num; this.number = number; } public int getNum() { return num; } public void setNum(int num) { this.num = num; } public String getNumber() { return number; } public void setNumber(String number) { this.number = number; } public int compareTo(Result o) { return this.number.compareTo(o.getNumber()); } } }

Cow Multiplication:

#include <iostream> #include <string> using namespace std; int main() { string s; string t; cin >> s; cin >> t; int a = 0; int b = 0; for (int i = 0; i < s.length(); i++) { char c = s[i]; a += atoi(&c); } for (int i = 0; i < t.length(); i++) { char c = t[i]; b += atoi(&c); } cout << a * b; return 0; }

Alternating Sum of Digits:

#include <iostream> #include <string> #include <iostream> #include <vector> #include <sstream> using namespace std; /** * 整形换成string */ string int2str(int &i) { string s; stringstream ss(s); ss << i; return ss.str(); } /** * 字符串转int */ int str2int(string &s) { return atoi(s.c_str()); } /** * 将x从n进制转换成m进制数 */ string convert(int x, int n, int m) { vector<int> vi; int y; while (x) { y = x % m; vi.push_back(y); x /= m; } string s; vector<int>::reverse_iterator rit = vi.rbegin(); for (; rit != vi.rend(); rit++) { if (*rit >= 10) { char temp = *rit - 10 + 'A'; s.append(&temp); } else { s.append(int2str(*rit)); } } return s; } /** * 将字符串代表的数由n进制转换成m进制 */ string convert(const char *str, int n, int m) { if (*str == '/0') return ""; int x = 0; int y; while (*str != '/0') { x *= n; if ((*str >= '0') && (*str <= '9')) { y = *str - '0'; } else if ((*str >= 'A') && (*str <= 'F')) { y = 10 + *str - 'A'; } else if ((*str >= 'a') && (*str <= 'f')) { y = 10 + *str - 'a'; } else { return ""; } if (y >= n) { return ""; } x += y; str++; } return convert(x, n, m); } int main() { int k; string n; cin >> k >> n; string num = convert(n.c_str(), k, 10); int t = str2int(num); string total; for (int i = 1; i <= t; i ++) { total.append(convert(i, 10, k)); } int j = 1; int final = 0; for (int i = 0; i < total.length(); i ++) { char c = total[i]; int a = atoi(&c); if (j == 0) { a = -a; j = 1; } else { j = 0; } final += a; } cout << final; return 0; }