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如果这篇博客帮助到你，可以请我喝一杯咖啡~
UPDATE：成绩单出了，看排名似乎考的没那么差 hh，原来不是我一个人觉得后两题难…
两年前打过第十三次 CSP 认证，当时觉得比赛挺水的就没继续打了…
两年后抱着（以为）自己进步一点的心态重新参赛，结果疯狂白给，100+100+100+60+25…特么还没两年前打得好。后两题完全只会暴力，字符串处理也是令人呕吐…
报数
// INFO BEGIN
//
// User = 201911505159(吴坎)
// Group = C/C++
// Problem = 报数
// Language = CPP11
// SubmitTime = 2019-12-15 13:53:06
//
// INFO END
#include <cstdio>
using namespace std;
const int N = 1e5 + 9;
int n, a[N];
int seven(int k)
{
if (k % 7 == 0)
return 1;
for (; k; k /= 10)
if (k % 10 == 7)
return 1;
return 0;
}
int main()
{
scanf("%d", &n);
for (int i = 0, k = 1; i < n; ++k)
{
if (seven(k))
++a[(k - 1) % 4];
else
++i;
}
for (int i = 0; i < 4; ++i)
printf("%d\n", a[i]);
return 0;
}
回收站选址
// INFO BEGIN
//
// User = 201911505159(吴坎)
// Group = C/C++
// Problem = 回收站选址
// Language = CPP11
// SubmitTime = 2019-12-15 13:51:03
//
// INFO END
#include <cstdio>
#include <set>
#include <vector>
using namespace std;
int n, cnt[5];
set<pair<int, int>> se;
int main()
{
scanf("%d", &n);
for (int i = 0; i < n; ++i)
{
pair<int, int> p;
scanf("%d%d", &p.first, &p.second);
se.insert(p);
}
for (auto p : se)
{
vector<pair<int, int>> v(4, p);
--v[0].first, ++v[1].first, --v[2].second, ++v[3].second;
if (se.count(v[0]) && se.count(v[1]) && se.count(v[2]) && se.count(v[3]))
{
--v[0].second;
++v[1].second;
++v[2].first;
--v[3].first;
int score = 0;
for (int i = 0; i < 4; ++i)
if (se.count(v[i]))
++score;
++cnt[score];
}
}
for (int i = 0; i < 5; ++i)
printf("%d\n", cnt[i]);
return 0;
}
化学方程式
// INFO BEGIN
//
// User = 201911505159(吴坎)
// Group = C/C++
// Problem = 化学方程式
// Language = CPP11
// SubmitTime = 2019-12-15 15:01:15
//
// INFO END
#include <cstdio>
#include <cstring>
#include <string>
#include <map>
#include <algorithm>
using namespace std;
const int N = 1023;
char s[N];
int pipei(int p)
{
for (int c = 0;; ++p)
{
if (s[p] == '(')
++c;
if (s[p] == ')')
--c;
if (!c)
return p;
}
}
void element(map<string, int> &mp, int coef, int l, int r)
{
mp[string(s + l, s + r + 1)] += coef;
}
void term(map<string, int> &mp, int coef, int l, int r)
{
void formula(map<string, int> & mp, int coef, int l, int r);
if (s[l] == '(' && s[r] == ')')
{
formula(mp, coef, l + 1, r - 1);
return;
}
element(mp, coef, l, r);
}
void term_ceof(map<string, int> &mp, int coef, int l, int r)
{
if ('0' <= s[r] && s[r] <= '9')
{
int pos = r, c = 0;
while ('0' <= s[pos] && s[pos] <= '9')
--pos;
for (int i = pos + 1; i <= r; ++i)
c = c * 10 + s[i] - '0';
if (c)
coef *= c;
term(mp, coef, l, pos);
return;
}
term(mp, coef, l, r);
}
void formula(map<string, int> &mp, int coef, int l, int r)
{
for (int i = l; i <= r;)
{
if (s[i] == '(')
{
int p = pipei(i) + 1;
if (p > r)
{
term_ceof(mp, coef, i, p - 1);
return;
}
while ('0' <= s[p] && s[p] <= '9')
++p;
term_ceof(mp, coef, i, p - 1);
i = p;
}
else
{
int p = i + 1;
while (('0' <= s[p] && s[p] <= '9') || ('a' <= s[p] && s[p] <= 'z'))
++p;
term_ceof(mp, coef, i, p - 1);
i = p;
}
}
}
void coef_formula(map<string, int> &mp, int l, int r)
{
if ('0' <= s[l] && s[l] <= '9')
{
int coef = 0, pos = l;
for (; '0' <= s[pos] && s[pos] <= '9'; ++pos)
coef = coef * 10 + s[pos] - '0';
formula(mp, coef, pos, r);
return;
}
formula(mp, 1, l, r);
}
map<string, int> expr(int l, int r)
{
map<string, int> mp;
int pre = l;
for (int i = l; i <= r; ++i)
if (s[i] == '+')
{
coef_formula(mp, pre, i - 1);
pre = i + 1;
}
coef_formula(mp, pre, r);
return mp;
}
int main()
{
int n;
for (scanf("%d", &n); n--;)
{
scanf("%s", s);
int eq = find(s, s + N, '=') - s;
printf(expr(0, eq - 1) == expr(eq + 1, strlen(s) - 1) ? "Y\n" : "N\n");
}
}
区块链
// INFO BEGIN
//
// User = 201911505159(吴坎)
// Group = C/C++
// Problem = 区块链
// Language = CPP11
// SubmitTime = 2019-12-15 17:25:00
//
// INFO END
#include <cstdio>
#include <vector>
#include <queue>
#include <tuple>
using namespace std;
const int N = 511;
struct Vertex
{
vector<int> to, link;
Vertex() : link(1, 0) {}
} v[N];
typedef tuple<int, vector<int>, int> tivi;
priority_queue<tivi, vector<tivi>, greater<tivi>> q;
char s[N];
int n, m, t, k;
void sync(int b)
{
if (q.empty() || get<0>(q.top()) > b)
return;
tivi u = q.top();
q.pop();
for (auto to : v[get<2>(u)].to)
if ((v[to].link.size() < get<1>(u).size()) ||
(v[to].link.size() == get<1>(u).size() &&
v[to].link.back() > get<1>(u).back()))
q.push(tivi(get<0>(u) + t, v[to].link = get<1>(u), to));
sync(b);
}
int main()
{
scanf("%d%d", &n, &m);
for (int i = 1, x, y; i <= m; ++i)
{
scanf("%d%d", &x, &y);
v[x].to.push_back(y);
v[y].to.push_back(x);
}
scanf("%d%d", &t, &k);
fgets(s, N, stdin);
for (int i = 1, a, b, c; i <= k; ++i)
{
fgets(s, N, stdin);
if (sscanf(s, "%d%d%d", &a, &b, &c) == 3)
{
sync(b);
v[a].link.push_back(c);
q.push(tivi(b + t, v[a].link, a));
}
else
{
sync(b);
printf("%d ", (int)v[a].link.size());
for (int j = 0; j < v[a].link.size(); ++j)
printf("%d ", v[a].link[j]);
printf("\n");
}
}
return 0;
}
魔数
// INFO BEGIN
//
// User = 201911505159(吴坎)
// Group = C/C++
// Problem = 魔数
// Language = CPP11
// SubmitTime = 2019-12-15 16:09:16
//
// INFO END
#include <cstdio>
using namespace std;
typedef long long ll;
const ll
N = 1e6 + 9,
u[5] = {
314882150829468584,
427197303358170108,
1022292690726729920,
1698479428772363217,
2006101093849356424},
fm[2] = {2009731336725594113, 2019};
ll mul(ll a, __int128 b, ll c) { return a * b % c; }
ll f1a[N];
int main()
{
int n, q;
scanf("%d%d", &n, &q);
for (int i = 1; i <= n; ++i)
f1a[i] = i;
for (int i = 1, l, r; i <= q; ++i)
{
scanf("%d%d", &l, &r);
int s = 0;
for (int j = l; j <= r; ++j)
s += f1a[j] % fm[1];
printf("%d\n", s);
ll ut = u[s % 5];
for (int j = l; j <= r; ++j)
f1a[j] = mul(f1a[j], ut, fm[0]);
}
return 0;
}