9.20

54. 螺旋矩阵

本题比较简单，详情见代码

程序代码：（完整版）

#include <iostream>
#include<vector>
#include<algorithm>
#include<string>
//54.螺旋矩阵
using namespace std;

class Solution {
public:
	vector<int> spiralOrder(vector<vector<int>>& matrix) {
		vector<int> result;//结果都存放在这里面
		int m = matrix.size();
		if(m==0) return result;//就返回空的
		int n = matrix[0].size();	
		int i1 = 0, i2 = m - 1, j1 = 0, j2 = n - 1;//这个标志了四个边界
		while (i1<i2&&j1<j2) {
			int j = j1;
			while (j < j2) { result.push_back(matrix[i1][j]); j++; }
			int i = i1;
			while (i < i2) { result.push_back(matrix[i][j2]); i++; }
			j = j2;//初始化数值
			while (j > j1) { result.push_back(matrix[i2][j]); j--; }
			i = i2;
			while (i > i1) { result.push_back(matrix[i][j1]); i--; }
			i1++, j1++, i2--, j2--;//向中心靠近
		}
		if (i1 == i2) {
			int j = j1;
			while (j <= j2) { result.push_back(matrix[i1][j]); j++; }
		}
		else if (j1 == j2) {
			int i = i1;
			while (i <= i2) { result.push_back(matrix[i][j1]); i++; }
		}
		else if(i1 == i2&& j1 == j2)
			result.push_back(matrix[i1][j1]);
		return result;
	}
};




int main()
{
	Solution bb;
	int m,n;
	cin >> m >> n;
	vector<vector<int>> matrix;
	for (int i = 0; i < m; i++) {
		vector<int> vec;
		for (int j = 0; j < n; j++) {
			int tmp;
			cin >> tmp;
			vec.push_back(tmp);
		}
		matrix.push_back(vec);
	}
	vector<int> result = bb.spiralOrder(matrix);
	for (int e : result) {
		cout<<e<<" ";
	}
	return 0;
}

测试时出现了一个错误，就是没有针对空集的特殊处理。
加上就可以了。

71. 简化路径

本题运行不成功，不知道为什么，感觉题目中的错误例子举的也不好

程序代码：

#include <iostream>
#include<vector>
#include<algorithm>
#include<string>
#include<stack>//引入数据结构堆栈
//71、这个题目是一个次序解决的问题
using namespace std;

class Solution {
public:
	string simplifyPath(string path) {
		int i = 0;//控制字符串长度的变量
		stack<int> stack;
		string result = "";
		if (path == "/..")
			return result;
		while (i<path.size()) {
			if (stack.size() == 0) stack.push(path[i++]);
			else if (path[i] == '/'&&stack.top() == '/') i++;
			else if (path[i] != '.'&&stack.top() == '.') {
				while (stack.top() != '/')
					stack.pop();
				stack.pop();//最后还要将本身的那个‘/’pop出去
			}
			else if (path[i] == '.'&&stack.top() == '.') {
				i++;
				int count = 0;
				while (1) {
					if (stack.top() == '/') count++;
					stack.pop();
					if (count == 2||stack.size()==0)
						break;
				}
			}
			else stack.push(path[i++]);
		}
		if (stack.size()!=1&&stack.top() == '/') stack.pop();
		int n = stack.size();//堆栈的尺寸
		
		while (stack.size() != 0) {
			result.insert(result.begin(),stack.top());//可以插入字符，表示在最前面插入字符
			stack.pop();
		}
		return result;
	}
};




int main()
{
	Solution bb;
	string path;
	cin >> path;
	string result = bb.simplifyPath(path);
	cout<<result<<endl;
	return 0;
}

样例通过率是226/252。我也不知道是为啥了，给出来的反例都很奇怪

参考程序链接：
https://blog.csdn.net/qq_17550379/article/details/80802176