题目描述

代码展示

//语言之争
#include<fstream>
#include<string>

using namespace std;

ifstream cin("language.in");
ofstream cout("language.out");

string a;
int n;

int main() {
    int i;
    bool java = false, cpp = false, word = false, err = false;
    cin >> a;
    n = a.size();

    for (i = 0; i < n; i++) {
        if (a[i] >= 'A' and a[i] <= 'Z')
            java = true;
        if (a[i] == '_')
            cpp = true;
    }

    if (a[0] >= 'A' and a[0] <= 'Z')
        java = false;
    for (i = 0; i < n; i++)
        if (a[i] == '_' and a[i + 1] == '_')
            cpp = false;

    if ((not java and not cpp) or (java and cpp))
        err = true;

    if (err)
        cout << "Error!\n";
    else {
        if (cpp)//change to java
        {
            word = false;
            for (i = 0; i < n; i++)
                if (word) {
                    cout << char(a[i] - 32);
                    word = false;
                }
                else if (a[i] >= 'a' and a[i] <= 'z')
                    cout << a[i];
                else if (a[i] == '_')
                    word = true;
        } else//change to cpp
        {
            for (i = 0; i < n; i++)
                if (a[i] >= 'A' and a[i] <= 'Z') {
                    if (i > 0) cout << "_";
                    cout << char(a[i] + 32);
                } else
                    cout << a[i];
        }
        cout << "\n";
    }
    cin.close();
    cout.close();
    return 0;
}