HJ106 字符逆序

#include <iostream>
#include <string>

void swap(std::string& s, int i, int j) {
    int len = s.length();
    if (i != j && (i >= 0 && i < len) && (j >= 0 && j < len)) {
        char tmp = '0';
        tmp = s[i];
        s[i] = s[j];
        s[j] = tmp;
    }
}
void reverse(std::string& s) {
    int len = s.length();
    for (int i = 0; i < (len / 2); ++i) {
        swap(s, i, len - i - 1);
    }
}

int main() {
    std::string in;
    while (getline(std::cin, in)) {
        reverse(in);
        std::cout << in << std::endl;
    }
    return 0;
}

解题思路:

难点1：仔细！

知识点：

知识点1：C++ reverse函数的用法;

#include <algorithm>
#include <string>

using namespace std;

int main() {
    string str = "hello world , hi";
    reverse(str.begin(), str.end());		//str结果为ih , dlrow olleh
    vector<int> v = {5, 4, 3, 2, 1};
    reverse(v.begin(), v.end());			//容器v的值变为1, 2, 3, 4, 5
}