[Coursera]算法基础_Week6_深搜（1）_Q2

#include <iostream>#include <stdio.h>#include <string.h>#include <stack>using namespace std;int p, q;int map[30][30];struct Point {int i;char a;Point(int i_, char a_) :i(i_), a(a_) {}};void Print(Point p) {cout << p.a << p.i;}stack<Point> s;int f(int i,int j) {int res=0;if (map[i - 1][j - 2] == 0) {map[i - 1][j - 2] = 1;res = f(i - 1, j - 2);if (res == 1) {int i_ = i - 1;char a_ = j + 63;s.push(Point(i_, a_));return 1;}map[i - 1][j - 2] = 0;res = 2;}if (map[i + 1][j - 2] == 0) {map[i + 1][j - 2] = 1;res = f(i + 1, j - 2);if (res == 1) {int i_ = i - 1;char a_ = j + 63;s.push(Point(i_, a_));return 1;}map[i + 1][j - 2] = 0;res = 2;}if (map[i - 2][j - 1] == 0) {map[i - 2][j - 1] = 1;res = f(i - 2, j - 1);if (res == 1) {int i_ = i - 1;char a_ = j + 63;s.push(Point(i_, a_));return 1;}map[i - 2][j - 1] = 0;res = 2;}if (map[i + 2][j - 1] == 0) {map[i + 2][j - 1] = 1;res = f(i + 2, j - 1);if (res == 1) {int i_ = i - 1;char a_ = j + 63;s.push(Point(i_, a_));return 1;}map[i + 2][j - 1] = 0;res = 2;}if (map[i - 2][j + 1] == 0) {map[i - 2][j + 1] = 1;res = f(i - 2, j + 1);if (res == 1) {int i_ = i - 1;char a_ = j + 63;s.push(Point(i_, a_));return 1;}map[i - 2][j + 1] = 0;res = 2;}if (map[i + 2][j + 1] == 0) {map[i + 2][j + 1] = 1;res = f(i + 2, j + 1);if (res == 1) {int i_ = i - 1;char a_ = j + 63;s.push(Point(i_, a_));return 1;}map[i + 2][j + 1] = 0;res = 2;}if (map[i - 1][j + 2] == 0) {map[i - 1][j + 2] = 1;res = f(i - 1, j + 2);if (res == 1) {int i_ = i - 1;char a_ = j + 63;s.push(Point(i_, a_));return 1;}map[i - 1][j + 2] = 0;res = 2;}if (map[i + 1][j + 2] == 0) {map[i + 1][j + 2] = 1;res = f(i + 1, j + 2);if (res == 1) {int i_ = i - 1;char a_ = j + 63;s.push(Point(i_, a_));return 1;}map[i + 1][j + 2] = 0;res = 2;}if (res == 0) {for (int x = 2; x <= q + 1; x++) {for (int y = 2; y <= p + 1; y++) {if (map[y][x] == 0)return 0;}}int i_ = i - 1;char a_ = j + 63;s.push(Point(i_, a_));return 1;}if (res == 2)return 0;}int main() {int n;cin >> n;int i = 1;while (i<=n) {memset(map, 0, sizeof(map));cin >> p >> q;for (int x = 0; x <= q + 3; x++) {map[0][x] = 1; map[1][x] = 1; map[p + 2][x] = 1; map[p + 3][x] = 1;}for (int x = 0; x <= p + 3; x++) {map[x][0] = 1; map[x][1] = 1; map[x][q + 2] = 1; map[x][q + 3] = 1;}map[2][2] = 1;int res = f(2,2);cout << "Scenario #" << i << ':' << endl;if (s.size() != 0) {while (s.size() != 0) {Print(s.top());s.pop();}cout << endl;}elsecout << "impossible" << endl;cout << endl;i++;}return 0;}