C语言编程练习7：字符串反转

思路：遇到空格就输出空格前的字符串，最后一个字符串单独输出

不用栈

#include <iostream>
#include <cstring>
using namespace std;

int main()
{
	char s[1005];
	int n;
	cin >> n;
	getchar();
	while (n--)
	{
		gets(s);
		int k = 0;
		int m = strlen(s);
		for (int i = 0; i < m; i++)
		{
			if (s[i] == ' ')
			{
			    for (int j = i - 1; j >= k; j--)
				{
					cout << s[j];
				}
				cout << " ";
				k = i + 1;
			}
		}
		for (int i = m - 1; i >= k; i--)
		{
			cout << s[i];
		}
		cout << endl;
	}
}

 用栈

#include <iostream>
#include <cstdio>
#include <string>
#include <algorithm>
#include <stack>

using namespace std;

int main()
{
    int n;
    cin>>n;
    getchar();
    while(n--)
    {
        string s;
        getline(cin,s);
        int len;
        len = (int)s.size();
        stack<char>st;
        for(int i=0;i<len;i++)
        {
            if(s[i]!=' ')
            {
                st.push(s[i]);
            }
            if(s[i]==' '||i==len-1)
            {
                while(!st.empty())
                {
                    printf("%c",st.top());
                    st.pop();
                }
                if(s[i]==' ')
                {
                    printf(" ");
                }

            }
        }
        printf("\n");
    }
    
    
    return 0;
}