# 暴力/练习

https://codeforces.com/contest/1293/problem/D

#include<bits/stdc++.h>
using namespace std;
#define ll long long
const int maxn = 1000;
const ll limit = 1e17;
ll x[maxn], y[maxn];

int main() {
ll  ax, bx, ay, by;
ll xs, ys, t;
cin >> x[0] >> y[0] >> ax >> ay >> bx >> by >> xs >> ys >> t;
int cnt = 0;
while(x[cnt]<(limit-bx+1)/ax&&y[cnt]<(limit-by+1)/ay) {
cnt++;
x[cnt] = x[cnt - 1] * ax + bx;
y[cnt] = y[cnt - 1] * ay + by;
}
ll ans = 0;
for (int i = 0; i <= cnt;i++) {
for (int j = 0; j <= cnt;j++) {
ll a = abs(xs - x[i]) + abs(ys - y[i]);
ll b = abs(x[i] - x[j]) + abs(y[i] - y[j]);
if(a<=t-b) {
ll m = abs(i - j) + 1;
ans = max(ans, m);
}
}
}
cout << ans << endl;
}


### 中缀表达式 Bracket Sequence

https://nanti.jisuanke.com/t/43466

#include<bits/stdc++.h>
using namespace std;
const long long mod = 1e9 + 7;
const int maxn = 3e5+10;
vector<long long> v[maxn];
int num(string s) {
int len = s.size();
int ret = 0;
for (int i = 0; i < len;i++) {
ret = ret * 10 + s[i] - '0';
}
return ret;
}
int main() {
int n;
scanf("%d", &n);
int cnt = 0;
for (int i = 1; i <= n;i++) {
string s;
cin >> s;
if(s[0]=='(') {
cnt++;
}
else if(s[0]==')') {
if(cnt%2==0) {
long long x = 0;
while(v[cnt].size()) {
x += v[cnt].back();
x %= mod;
v[cnt].pop_back();
}
cnt--;
v[cnt].push_back(x);
}
else {
long long x = 1;
while(v[cnt].size()) {
x *= v[cnt].back();
x %= mod;
v[cnt].pop_back();
}
cnt--;
v[cnt].push_back(x);
}
}
else{
int x = num(s);
v[cnt].push_back(x);
}
}

long long ans = 0;
while(v[0].size()) {
ans = ans + v[0].back();
ans %= mod;
v[0].pop_back();
}
printf("%lld\n", ans);
}


### [CF1175B] catch overflow

#include<bits/stdc++.h>
using namespace std;
const long long limit = ((long long)1 << 32) - 1;

int main() {
int n;
scanf("%d", &n);
long long ans = 0,t = 1;
int f = 0, cnt = 0;
vector<long long> v;
for (int i = 1; i <= n;i++) {
string s;
cin >> s;
if(s[0]=='a') {
ans += t;
if(ans>limit) {
f = 1;
}
}
if(s[0]=='f'){
int x;
scanf("%d", &x);
if(t>limit){
cnt++;
continue;
}
t *= x;
v.push_back(x);
}
if(s[0]=='e') {
if(cnt==0){
t /= v.back();
v.pop_back();
}
else
cnt--;
}
}
if(f)
printf( "OVERFLOW!!!\n" );
else
cout << ans << endl;
}


### NowCoder 非递归实现组合型枚举

#include<bits/stdc++.h>
using namespace std;
const int maxn = 1e5 + 100;
vector<int> v;
int n, m;
/*
void cal(int x){//参数x表示当前选择的数字
if(v.size()>m||v.size()+(n-x+1)<m)
return;
if(x==n+1){
for (int i = 0; i < v.size();i++){
printf("%d ", v[i]);
}
printf("\n");
return;
}
//选x
v.push_back(x);
cal(x + 1);
//不选x
v.pop_back();
cal(x + 1);
return;
}*/

int old_top = top;
st[++top] = x;
st[++top] = old_top;
}
int ret(){
int ret_addr = st[top - 1];
top = st[top];//让最后一条语句出栈
}
int main(){
cin >> n >> m;
cal(1, 0);//数字1进栈
while(top){
int x = st[top - 2]; //获取的是数字x
case 0:
if(v.size()>m||v.size()+(n-x+1)<m){
continue;
}
if(x==n+1){
for (int i = 0; i < v.size();i++){
printf("%d ", v[i]);
}
printf("\n");
continue;
}
v.push_back(x);
cal(x + 1, 1);
continue;
case 1:
v.pop_back();
cal(x + 1, 2);//返回后从cas2继续执行
continue;
case 2:
}
}
}


# 其他

## 语法

### 断言

int a = 0;
assert(a==0);

assert(a==1);



## 最大子段和

int best=0,sum=0;
for(int i=0;i<n;i++)
{
sum=max(array[i],sum+array[k]);
best=max(sun,best);
}
cout<<best<<endl;


## 双指针问题

### [CF1304D]Shortest and Longest LIS

https://codeforces.com/contest/1304/problem/D

#include<bits/stdc++.h>
using namespace std;

const int maxn = 2e5 + 100;
int ans[maxn];
int main() {
int T;
scanf("%d", &T);
while(T--) {
int n;string s;
cin >> n >> s;
int num = n, last = 0;
for (int i = 0; i < n;i++) {
if(i==n-1||s[i]=='>') {
for (int j = i; j >= last;j--) {
ans[j] = num--;
}
last = i + 1;
}
}
for (int i = 0; i < n;i++) {
printf("%d ", ans[i]);
}
printf("\n");
num = 1, last = 0;
for(int i=0;i<n;i++) {
if(i==n-1||s[i]=='<') {
for (int j = i; j >= last;j--) {
ans[j] = num++;
}
last = i + 1;
}
}
for (int i = 0; i < n;i++) {
printf("%d ", ans[i]);
}
printf("\n");
}
}


### [CF1199C] mp3

https://codeforces.com/contest/1199/problem/C

#include<bits/stdc++.h>
using namespace std;
#define ll long long
const int maxn = 4e5 + 100;
vector<int> v;
map<int, int> mp;
int pre[maxn];
int main() {
int n, k;
scanf("%d%d", &n, &k);
k *= 8;
int m = 0;
for (int i = 1; i <= n;i++) {
int x;
scanf("%d", &x);
if(!mp[x]) {
v.push_back(x);
}
mp[x]++;
}
sort(v.begin(), v.end());
m = unique(v.begin(), v.end())-v.begin();
int tot = k / n;
if(tot>20)
tot = 20;
tot = 1 << tot;
for (int i = 0; i < m;i++){
if(i==0)
pre[i] = mp[v[i]];
else
pre[i] = pre[i - 1] + mp[v[i]];
}
int ans = 0x3f3f3f3f;
for (int i = 0; i < m;i++) {
int j = i + tot - 1;
int x = 0;
if(i!=0)
x = pre[i - 1];
if(j>=m) {
ans = min(ans, x);
break;
}
int y = pre[j];
ans = min(ans, pre[m - 1] - y + x);
}
ans = max(ans, 0);
cout<<ans<<endl;
}

posted @ 2020-03-28 00:10  瓜瓜站起来  阅读(200)  评论(0编辑  收藏  举报