#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <utility>
#include <algorithm>
#include <vector>

    // strlen strdup strcpy strncpy strcat

#define T printf("%s body='%s'\n", __PRETTY_FUNCTION__, body)

class str {
public:
    str(const char *val = "") {
        body = strdup(val);
        T;
    }

    ~str() {
        if (body == nullptr) return;
        T;
        free(body);
    }

    void print() const {
        printf("[%s]\n", body);
    }

    str & operator= (const str &b) {
        free(body);
        body = strdup(b.body);
        T;
        return *this;
    }

    str(const str &b) {
        body = strdup(b.body);
        T;
    }

#if 1
    str(str &&b) {  // конструктор по r-value
        body = b.body;  // b - временный.
        b.body = nullptr;
        T;
    }

    str &operator=(str &&b) { // Копирование из r-value - можно просто забрать его поля.
        if (this == &b) return *this;
        free(body);
        body = b.body;
        b.body = nullptr;
        T;
        return *this;
    }
#endif

    str operator+ (const str &b) const {
        T;
        size_t need = strlen(body) + strlen(b.body) + 1;
        str ret("");
        ret.body = (char *)realloc(ret.body, need);
        assert(ret.body != nullptr); 
        strcpy(ret.body, body);
        strcat(ret.body, b.body);
        return ret;
    }
    bool operator<(str const &oth) const {
        return strcmp(body,oth.body) < 0;
    }
private:
    char *body;         // C-string, null-terminated "123" -> '1', '2', '3', 0
};



void foo(str c) {
    printf("foo!");
    c.print();
}

#if 1
void myswap(str &l, str &r) {
    str t = std::move(l);
    l = std::move(r);
    r = std::move(t);
}
#else
void myswap(str &l, str &r) {
    str t = l;
    l = r;
    r = t;
}
#endif

int main() {
#if 0
    str a("abra");
    str b("shvabra");
    str c;
    c = a + b;
    myswap(a,a);
    a.print();
    b.print();
    // str c = a + b;
#endif
    std::vector<str> aaa;
    aaa.emplace_back(str("shvabra"));
    aaa.emplace_back(str("abra"));
    aaa.emplace_back(str("cadabra"));
    aaa.emplace_back(str("foo"));
    printf("======= sorting =====\n");
    std::sort(aaa.begin(), aaa.end());
    
}