记录编号	569953	评测结果	AAAAAAA
题目名称	[USACO 2.3.3]零数列	最终得分	100
用户昵称	lihaoze	是否通过	通过
代码语言	C++	运行时间	0.000 s
提交时间	2022-03-19 22:31:24	内存使用	0.00 MiB

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cstring>
#include <vector>
#include <string>
#define OPEN(_x) freopen(#_x".in", "r", stdin); freopen(#_x".out", "w", stdout)
#define MAX(_a, _b) [&](int __a, int __b) { return __a < __b ? __b : __a; }((_a), (_b))
#define MIN(_a, _b) [&](int __a, int __b) { return __a > __b ? __b : __a; }((_a), (_b))
#define ABS(_x) [&](int __x) { return __x < 0 ? -__x : __x; }(_x)
#define fi first
#define se second 

using ll = long long;
using PII = std::pair<int, int>;

namespace IO {
    template <typename T> inline T read() {
        char ch = getchar();
        T ret = 0, sig = 1;
        while(ch < '0' || ch > '9') { if(ch == '-') sig = -1; ch = getchar(); }
        while(ch >= '0' && ch <= '9') ret *= 10, ret += ch - 48, ch = getchar();
        return ret * sig;
    }
    template <typename T> inline void write(T out) {
        if(!out) { putchar('0'), putchar(' '); return; }
        int stk[100], tt = 0;
        if(out < 0) out = -out, putchar('-');
        while(out) stk[tt++] = out % 10, out /= 10;
        for(register int i = --tt; i>=0; --i) putchar(stk[i] + 48);
        putchar(' ');
    }
    template <typename T> inline void read(T& ret) { ret = IO::read<T>(); }
    template <typename T, typename... Args> inline void read(T& x, Args&... args) { IO::read(x), IO::read(args...); }
    template <typename T, typename... Args> inline void write(T x, Args... args)  { IO::write(x), IO::write(args...); }
};


int n;
std::vector<char> chosen;
std::vector<std::string> ans;

inline bool check() {
    int now = 1, x = 0;
    char sig = '+';
    for (register int i = 0; i<n; ++i) {
        if(chosen[i] != ' ') x += now * (sig == '+' ? 1 : -1), now = i + 2, sig = chosen[i];
        else now = now * 10 + i + 2;
    }
    return !x;
}

void dfs(int a) {
    if(a == n) {
        if(check()) {
            std::string str;
            str += 49;
            int cnt = 2;
            for (auto i : chosen) {
                str += i, str += (cnt ++) + 48;
            }
            ans.emplace_back(str);
        }
        return;
    }

    chosen.emplace_back('+');
    dfs(a + 1);
    chosen.pop_back();

    chosen.emplace_back('-');
    dfs(a + 1);
    chosen.pop_back();

    chosen.emplace_back(' ');
    dfs(a + 1);
    chosen.pop_back();
}

int main() {
    #ifdef DEBUG
    OPEN(test);
    #endif
    OPEN(zerosum);
    IO::read(n);
    dfs(1);
    std::sort(ans.begin(), ans.end());
    for (auto i : ans) puts(i.c_str());
    return 0;
}