Gym 101190H Hard Refactoring (模拟坑题)

Posted 2020-10-04 dwtfukgv

题意：给定 n 个区间，让你进行合并，问你最后的区间是，如果是空集，输出 false 如果区间是是 [-32768，32767] ，则是true。

析：进行区间合并，要注意，如果是 x >= 0 && x <= 32767 那么输出是  x >= 0，在这地方，真是错死了。。。。。。后来看了数据才知道有这个，其他的就是进行区间合并，如果第 i 个和第 j 个区间合并时，假设 x >= a && x <= b  || x >= c && x <= d，那么如果 b+1 >= c && a <= c || d+1 >= a && c <= a  就进行合并，当然对于单向的就进行一个标记左端点是-32768右端点是32767，也就是最后在输出。

代码如下：

#pragma comment(linker, "/STACK:1024000000,1024000000")
#include <cstdio>
#include <string>
#include <cstdlib>
#include <cmath>
#include <iostream>
#include <cstring>
#include <set>
#include <queue>
#include <algorithm>
#include <vector>
#include <map>
#include <cctype>
#include <cmath>
#include <stack>
#include <sstream>
#include <list>
#include <assert.h>
#include <bitset>
#define debug() puts("++++");
#define gcd(a, b) __gcd(a, b)
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1
#define fi first
#define se second
#define pb push_back
#define sqr(x) ((x)*(x))
#define ms(a,b) memset(a, b, sizeof a)
#define sz size()
#define pu push_up
#define pd push_down
#define cl clear()
#define all 1,n,1
#define FOR(x,n)  for(int i = (x); i < (n); ++i)
#define freopenr freopen("in.txt", "r", stdin)
#define freopenw freopen("out.txt", "w", stdout)
using namespace std;

typedef long long LL;
typedef unsigned long long ULL;
typedef pair<int, int> P;
const int INF = 0x3f3f3f3f;
const LL LNF = 1e15;
const double inf = 1e20;
const double PI = acos(-1.0);
const double eps = 1e-8;
const int maxn = 1000 + 500;
const LL mod = 1e9 + 7;
const int dr[] = {-1, 0, 1, 0};
const int dc[] = {0, 1, 0, -1};
const char *de[] = {"0000", "0001", "0010", "0011", "0100", "0101", "0110", "0111", "1000", "1001", "1010", "1011", "1100", "1101", "1110", "1111"};
int n, m;
const int mon[] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
const int monn[] = {0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
inline bool is_in(int r, int c) {
  return r >= 0 && r < n && c >= 0 && c < m;
}

struct Node{
  int small, big;
  bool flag;
};

Node a[maxn];

int clac(const string &s){
  int ans = 0;
  int sig = s[0] == ‘-‘ ? -1 : 1;
  ans = s[0] == ‘-‘ ? 0 : s[0] - ‘0‘;
  for(int i = 1; i < s.sz; ++i)
    ans = ans * 10 + s[i] - ‘0‘;
  return ans * sig;
}

vector<Node> ans;

int main(){
  freopen("hard.in", "r", stdin);
  freopen("hard.out", "w", stdout);
  string s;
  int idx = 0;
  while(getline(cin, s)){
    a[idx].flag = 0;
    if(s[2] == ‘>‘){
      stringstream ss(s);
      string t;
      ss >> t;  ss >> t;
      ss >> t;
      a[idx].big = clac(t);
      if((ss >> t)) {
        if(t == "||")  a[idx].small = 32767;
        else{
          ss >> t >> t;
          ss >> t;
          a[idx].small = clac(t);
        }
      }
      else  a[idx].small = 32767;
    }
    else{
      stringstream ss(s);
      string t;
      ss >> t;  ss >> t;
      ss >> t;
      a[idx].small = clac(t);
      a[idx].big = -32768;
    }
      if(a[idx].big < -32768 || a[idx].small > 32767)  a[idx].flag = 1;
    ++idx;
  }

  bool ok = false;
  for(int i = 0; i < idx; ++i){
    if(a[i].small >= a[i].big){
        ok = true;
    }
  }

  if(!ok){  puts("false");  return 0; }


  for(int k = 0; k < 10; ++k)
    for(int i = 0; i < idx; ++i){
      if(a[i].small < a[i].big)  a[i].flag = 1;
      if(a[i].flag)  continue;
      for(int j = 0; j < idx; ++j){
        if(a[j].small < a[j].big)  a[j].flag = 1;
        if(i == j)  continue;
        if(a[j].flag)  continue;
        if(a[i].big <= a[j].small+1 && a[i].small >= a[j].small || a[j].big <= a[i].small+1 && a[i].small <= a[j].small){
          a[i].small = max(a[i].small, a[j].small);
          a[i].big = min(a[i].big, a[j].big);
          a[j].flag = 1;
        }
      }
    }

  for(int i = 0; i < idx; ++i)
    if(!a[i].flag)  ans.pb(a[i]);


  if(ans[0].small == 32767 && ans[0].big == -32768)  puts("true");
  else {
    for(int i = 0; i < ans.sz; ++i){
      if(ans[i].big > -32768){
        printf("x >= %d", ans[i].big);
        if(ans[i].small < 32767)  printf(" && x <= %d", ans[i].small);
      }
      else printf("x <= %d", ans[i].small);
      if(i != ans.sz-1)  printf(" ||");
      puts("");
    }
  }

  return 0;
}