7530
题意:填3*3的格子,让给的六个单词在横竖都有。
思路:(AC)深搜生成 P(6,3)的排列,带入检验即可。
#include <iostream>
#include <cstring>
using namespace std;
int arr[6], vis[6], have[6];
string given[6], atry[3], tmp;
bool flag;
void dfs(int cur)
{
if (flag) return ;
if (cur == 3)
{
memset(have, 0, sizeof(have));
for (int i = 0; i < 3; ++ i)
{
atry[i] = given[arr[i]];
have[arr[i]] = 1;
}
for (int i = 0; i < 3; ++ i)
{
tmp = "";
for (int j = 0; j < 3; ++ j)
tmp += atry[j][i];
for (int j = 0; j < 6; ++ j)
{
if (have[j] == 0 && given[j] == tmp)
{
have[j] = 1;
break;
}
}
}
bool f = true;
for (int i = 0; i < 6; ++ i)
{
if (have[i] == 0)
{
f = false;
break;
}
}
if (f)
{
for (int i = 0; i < 3; ++ i)
cout << atry[i] << endl;
flag = true;
}
}
else
{
for (int i = 0; i < 6; ++ i) if (!vis[i])
{
arr[cur] = i;
vis[i] = true;
dfs(cur+1);
vis[i] = false;
}
}
}
int main()
{
while (cin >> given[0])
{
flag = false;
memset(vis, 0, sizeof(vis));
for (int i = 1; i < 6; ++ i)
cin >> given[i];
dfs(0);
if (!flag) cout << 0 << endl;
}
}
7531
题意:n个串,每个串有Ni个环,每个环都可以解开然后套住两个环,问至少需要解开多少个环才能让n个串变成一个串
思路:(AC)每次都在最少的环的串上解开一个环,套住最长的两个串
#include <cstdio>
#include <algorithm>
using namespace std;
int n, arr[500010], top, tail, ans;
int main()
{
while (scanf("%d", &n) != EOF)
{
for (int i = 0; i < n; ++ i)
scanf("%d", &arr[i]);
sort(arr, arr+n);
top = 0;
tail = n-1;
ans = 0;
while (tail > top)
{
arr[top] --;
if (arr[top] == 0) top ++;
ans ++;
tail --;
}
printf("%d\n", ans);
}
}
7532
题意:N盘菜,每盘菜都有两个价格Ai,Bi,如果第一个点k菜,那么消费Ai,否则消费Bi,问点1~N盘菜最少需要消费多少(每盘菜做多点一次)
思路:(AC)显然,价格Bi是主价格,我根据加个Bi对所有菜进行排序,对于点K盘菜,有两种可能使消费最少:1. 点前K盘菜,最后消费为前K盘菜的Bi的和 + 前K盘菜中Ai-Bi 最小值 2.消费后N-K盘菜中Ai最小的一盘菜 和 前K-1盘菜。两者取较小值即答案。
#include <vector>
#include <cstdio>
#include <algorithm>
using namespace std;
#define N 500000
#define Min(a,b) ((a)<(b)?(a):(b))
typedef long long LL;
typedef pair<int,int> pii;
pii data[N];
int n, fstMin[N], disMin[N];
LL sndSum[N];
bool cmp(pii a, pii b)
{
if (a.second < b.second) return true;
if (a.second > b.second) return false;
return a.first < b.first;
}
int main()
{
while (scanf("%d", &n) != EOF)
{
for (int i = 0; i < n; ++ i)
scanf("%d%d", &data[i].first, &data[i].second);
sort(data, data+n, cmp);
sndSum[0] = data[0].second;
for (int i = 1; i < n; ++ i)
sndSum[i] = sndSum[i-1] + data[i].second;
fstMin[n-1] = data[n-1].first;
for (int i = n-2; i >= 0; -- i)
fstMin[i] = Min( fstMin[i+1], data[i].first );
disMin[0] = data[0].first - data[0].second;
for (int i = 1; i < n; ++ i)
disMin[i] = Min( disMin[i-1], data[i].first-data[i].second );
for (int i = 0; i < n; ++ i)
{
long long v1 = sndSum[i] + disMin[i];
long long v2 = fstMin[i];
if (i != 0) v2 += sndSum[i-1];
printf("%lld\n", Min( v1,v2 ));
}
}
}
7533
题意:求1~N这N个数的一个序列,满足M个要求,每个要求描述了位置x~位置y的最大值或者最小值。
思路:(AC)显然这样的序列可能多种。我只要找出每个位置可能的值,再做一次最大匹配即可。
#include <cstdio>
#include <cstring>
#define N 205
#define min(a,b) (a)<(b)?(a):(b)
#define max(a,b) (a)<(b)?(b):(a)
int n, k, tag, x, y, v;
int minn[N], maxn[N], st[N], ed[N];
bool bmap[N][N], bmask[N];
int cx[N], cy[N];
int findpath( int u ) {
for (int i = 1; i <= n; ++ i) {
if (bmap[u][i] && !bmask[i]) {
bmask[i] = true;
if (cy[i] == -1 || findpath( cy[i] )) {
cy[i] = u;
cx[u] = i;
return 1;
}
}
}
return 0;
}
bool maxmatch() {
int res = 0;
memset(cx, -1, sizeof(cx));
memset(cy, -1, sizeof(cy));
for (int i = 1; i <= n; ++ i) {
if (cx[i] == -1) {
for (int j = 1; j <= n; ++ j) {
bmask[j] = 0;
}
res += findpath(i);
}
}
return res == n;
}
int main() {
while (scanf("%d%d",&n,&k) != EOF) {
for (int i = 1; i <= n; ++ i) {
minn[i] = 1;
maxn[i] = n;
st[i] = 1;
ed[i] = n;
}
while (k --) {
scanf("%d%d%d%d",&tag,&x,&y,&v);
if (x > y) {
int t = x;
x = y;
y = t;
}
st[v] = max(st[v], x);
ed[v] = min(ed[v], y);
if (tag == 1) {
for (int i = x; i <= y; ++ i) {
maxn[i] = min(maxn[i],v);
}
}
else {
for (int i = x; i <= y; ++ i) {
minn[i] = max(minn[i],v);
}
}
}
memset(bmap, false, sizeof(bmap));
for (int i = 1; i <= n; ++ i) {
for (int j = minn[i]; j <= maxn[i]; ++ j) {
if (st[j] <= i && ed[j] >= i) {
bmap[i][j] = true;
}
}
}
if (maxmatch()) {
for (int i = 1; i <= n; ++ i) {
printf("%d%c", cx[i], i==n?'\n':' ');
}
}
else printf("-1\n");
}
}
7534
题意:有1~N这N个办公楼,给K个指令,指令分两种,1.基础结余为B 日盈利P 的公司在D 天搬入办公楼O,2. 查询X到Y办公楼在D日结余最多的办公楼的结余。当然,如果一个办公楼已经有了公司,但是又搬进了新公司,那么当然结余为新公司的结余,并且新公司要到第二天才开始盈利。查询是在D日办公结束后查询。
思路:(TLE)模拟,每一次询问都更新所有公司的结余。如果是查询操作,就遍历之间所有办公楼找到最大值。
#include <cstdio>
typedef long long LL;
int n, m;
LL maxn;
int tag, t, a, b, k, z, s, pt;
struct Office {
LL balance;
int profit;
bool flag;
void init() { balance = profit = 0; flag = false; }
void set(int _b, int _p) { balance = _b; profit = _p; flag = true; }
void add(int day) { balance += profit*day; }
} office[100005];
int main() {
freopen("in.txt","r",stdin);
freopen("out.txt","w",stdout);
while (scanf("%d%d",&n,&m) != EOF) {
for (int i = 1; i <= n; ++ i) {
office[i].init();
}
pt = -1;
while (m --) {
scanf("%d", &tag);
if (tag == 1) {
scanf("%d%d%d%d",&t,&k,&z,&s);
office[k].set(s, z);
if (pt) {
for (int i = 1; i <= n; ++ i) {
if (i != k && office[i].flag) {
office[i].add( t-pt );
}
}
}
pt = t;
}
else {
scanf("%d%d%d",&t,&a,&b);
if (a > b) {
tag = a;
a = b;
b = tag;
}
if (pt) {
for (int i = 1; i <= n; ++ i) {
if (office[i].flag) {
office[i].add( t-pt );
}
}
}
pt = t;
bool f = false;
for (int i = a; i <= b; ++ i) {
if (office[i].flag) {
if (!f) {
maxn = office[i].balance;
f = true;
}
else if (maxn < office[i].balance) {
maxn = office[i].balance;
}
}
}
if (f) printf("%lld\n", maxn);
else printf("nema\n");
}
}
}
}