ACM Steps @ HDOJ
HDOJ最近新推出的ACM Steps功能，支持一下。
虽然已经不再参加ACM/ICPC竞赛了，平时也不太做题了。
：现在就偶尔逛一下HDOJ，偶尔有兴致找几道简单易读的题写一下，练一下，
老菜鸟一个，不再以参赛为目的。
ACM Steps很好的一个功能，打算从Chapter One开始记录一下自己的ACM Steps路程。
记录一些代码，这样也能方便自己查看。
：pass 因为不经常做了，所以可能会比较长一段时间才记录一次，呵呵。
ACM Steps题库是基础题库+随机题库， 所以不同ID见到的题库可能不一样（随机题库部分）。
所以我记录的只是我个人看到的题库。
：pass 最近一段时间OJ咋经常上不去yo。
昨天参加了腾讯实习生杭州站搜索开发的第一轮面试，唉，基础弱，各种不会，饿补ing。
也是第一次参加面试，处女面就这样献给扣扣了。攒经验为主，希望有个好的开始呗。
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Forget-Wind's Chapter One：
第一章节，基本是比较简单的一些题，所以本章节基本只记录代码，不做描述性的解题报告。
1.1.1 - 1.1.8 基本输入输出
1.2.1 Elevator ----------- HDOJ 1008 (对应的外部题库链接，下面直接链接到对应的外部题库)
#include <stdio.h>
int main() {
int n, pref, floor, sum;
while (scanf("%d", &n) == 1) {
if (n == 0) break;
pref = 0;
sum = 0;
for (int i = 0; i < n; i++) {
scanf("%d", &floor);
if (floor > pref) {
sum += 6 * (floor - pref);
} else {
sum += 4 * (pref - floor);
}
pref = floor;
sum += 5;
}
printf("%d\n", sum);
}
}
1.2.2 Biker's Trip Odometer
#include <stdio.h>
#define pi 3.1415927
#define c_mile (5280 * 12.0)
#define c_ti (60 * 60)
int main() {
double dia, rev, ti;
int cas = 0;
while (scanf("%lf %lf %lf", &dia, &rev, &ti) == 3) {
if (rev == 0) break;
double total = pi * dia * rev / c_mile;
ti /= c_ti;
double ave = total / ti;
printf("Trip #%d: ", ++cas);
printf("%.2lf %.2lf\n", total, ave);
}
return 0;
}
1.2.3 Climbing Worm
#include <stdio.h>
int main() {
int n, u, d;
while (scanf("%d %d %d", &n, &u, &d) != EOF) {
if (n == 0 && u == 0 && d == 0) break;
if ((n - u) % (u - d) == 0)
printf("%d\n", 2 * (n - u) / (u - d) + 1);
else
printf("%d\n", 2 * ((n - u) / (u - d)) + 3);
}
return 0;
}
1.2.4 Rightmost Digit
(二分求幂，很久没写了，所以非递归形式的忘了怎么写，就循着思路写了个递归形式的二分加速。
当然，这题也可以通过找规律去做。)
#include <stdio.h>
int binary_exp(int base, int exp) {
if (exp == 0)
return 1;
if (exp & 1) {
return (base * binary_exp(base, exp - 1)) % 10;
} else {
exp >>= 1;
int tmp = binary_exp(base, exp) % 10;
return (tmp * tmp) % 10;
}
}
int main() {
int test, n;
scanf("%d", &test);
while (test--) {
scanf("%d", &n);
int base = n % 10, exp = n;
printf("%d\n", binary_exp(base, exp));
}
return 0;
}
1.2.5 Quicksum
#include <stdio.h>
int main() {
char str[300];
while (gets(str)) {
if (str[0] == '#') break;
int sum = 0;
for (int i = 0; str[i]; i++) {
if (str[i] != ' ')
sum += (str[i] - 'A' + 1) * (i + 1);
}
printf("%d\n", sum);
}
return 0;
}
1.2.6 Balloon Comes!
#include <stdio.h>
void Print(double a, double b, char op) {
double sum = 0.0;
if (op == '+') {
sum = a + b;
} else if (op == '-') {
sum = a - b;
} else if (op == '*') {
sum = a * b;
} else {
sum = a / b;
}
if (sum == (int)sum) {
printf("%d\n", (int)sum);
} else {
printf("%.2lf\n", sum);
}
}
int main() {
int test;
scanf("%d", &test);
while (test--) {
char op[2];
double a, b;
scanf("%s %lf %lf", op, &a, &b);
Print(a, b, op[0]);
}
return 0;
}
1.2.7 Identity Card
#include <cstdio>
#include <cstring>
#include <string>
using namespace std;
string name[] = {"Zhejiang", "Beijing", "Taiwan", "Hong Kong",
"Macao", "Tibet", "Liaoning", "Shanghai"};
string id[] = {"33", "11", "71", "81", "82", "54", "21", "31"};
int main() {
int test;
char str[50];
scanf("%d", &test);
while (test--) {
scanf("%s", str);
printf("He/She is from ");
for (int i = 0; i < 8; i++) {
if (strncmp(str, id[i].c_str(), 2) == 0) {
printf("%s", name[i].c_str());
}
}
printf(",and his/her birthday is on ");
printf("%c%c,%c%c,%c%c%c%c",
str[10], str[11], str[12], str[13], str[6], str[7], str[8], str[9]);
printf(" based on the table.\n");
}
return 0;
}
1.2.8 AC Me
#include <cstdio>
#include <cstring>
using namespace std;
char str[100010];
int num[250];
int main() {
while (gets(str)) {
memset(num, 0, sizeof(num));
for (int i = 0; str[i]; i++) {
num[str[i]]++;
}
for (int i = 'a'; i <= 'z'; i++) {
printf("%c:%d\n", i, num[i]);
}
puts("");
}
return 0;
}
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1.3 之后开始接触C++标准程序库自修教程这么书，所以可能开始去用到一些STL。
以前自己做ACM基本是不会用也不去用。1.3小节基本是一些简单的贪心题。
1.3.1 FatMouse' Trade （贪心）
#include <iostream>
#include <iomanip>
#include <vector>
#include <algorithm>
using namespace std;
struct FatMouse {
int javaBean;
int catFood;
double perFood;
FatMouse(int a, int b, double c)
: javaBean(a), catFood(b), perFood(c) {}
bool friend operator < (const FatMouse &a, const FatMouse &b) {
return a.perFood > b.perFood;
}
};
vector<FatMouse> fatmouse;
int main() {
int m, n, a, b;
while (cin >> m >> n) {
if (m < 0 && n < 0)
break;
for (int i = 0; i < n; ++i) {
cin >> a >> b;
fatmouse.push_back(FatMouse(a, b, a * 1.0 / b));
}
sort(fatmouse.begin(), fatmouse.end());
double ret = 0.0, leftFood = m;
for (int i = 0; i < n; ++i) {
if (leftFood >= fatmouse[i].catFood) {
ret += fatmouse[i].javaBean;
leftFood -= fatmouse[i].catFood;
} else {
ret += leftFood * fatmouse[i].perFood;
break;
}
}
cout << setiosflags(ios::fixed) << setprecision(3) << ret << endl;
fatmouse.clear();
}
return 0;
}
1.3.2 Moving Tables （找最大重叠数）
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
#define RR(x) (((x) + 1) >> 1)
struct Room {
int corridor1;
int corridor2;
Room(int a, int b) : corridor1(RR(a)), corridor2(RR(b)) {
if (corridor1 > corridor2) {
corridor1 ^= corridor2;
corridor2 ^= corridor1;
corridor1 ^= corridor2;
}
}
};
int main() {
int test, n,a , b;
cin >> test;
while (test--) {
cin >> n;
vector<int> hash(201);
for (int i = 0; i < n; ++i) {
cin >> a >> b;
Room tmp(a, b);
for (int j = tmp.corridor1; j <= tmp.corridor2; ++j) {
hash[j]++;
}
}
vector<int>::iterator pos;
pos = max_element(hash.begin(), hash.end());
cout << *pos * 10 << endl;
}
return 0;
}
1.3.3 今年暑假不AC （贪心，按结束时间排序，仿函数做排序准则）
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
struct TV {
int st;
int ed;
TV(int a, int b) : st(a), ed(b) {}
};
class cmp {
public:
bool operator() (const TV &a, const TV &b) const {
return a.ed < b.ed;
}
};
vector<TV> show;
int main() {
int n, a, b;
while (cin >> n, n) {
for (int i = 0; i < n; i++) {
cin >> a >> b;
show.push_back(TV(a, b));
}
sort(show.begin(), show.end(), cmp());
int cnt = 1;
vector<TV>::const_iterator pre = show.begin();
vector<TV>::const_iterator pos = show.begin() + 1;
for ( ; pos != show.end(); ++pos) {
if (pos->st >= pre->ed) {
cnt++;
pre = pos;
}
}
cout << cnt << endl;
show.clear();
}
return 0;
}
1.3.4 百步穿杨（简单模拟）
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
struct Arrow {
int length;
int cnt;
Arrow(int a, int b) : length(a), cnt(b) {}
};
class cmp {
public:
bool operator() (const Arrow &a, const Arrow &b) const {
return a.length < b.length;
}
};
vector<Arrow> arrow;
int main() {
int test, n, a, b;
cin >> test;
while (test--) {
cin >> n;
for (int i = 0; i < n; i++) {
cin >> a >> b;
arrow.push_back(Arrow(a, b));
}
sort(arrow.begin(), arrow.end(), cmp());
vector<Arrow>::const_iterator pos;
for (pos = arrow.begin(); pos != arrow.end(); ++pos) {
for (int i = 0; i < pos->cnt; i++) {
cout << ">+";
for (int j = 0; j < pos->length - 2; j++) {
cout << "-";
}
cout << "+>" << endl;
}
cout << endl;
}
arrow.clear();
}
}
1.3.5 第二小整数 （用了stl的nth_element）
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
int main() {
int test, n, a;
vector<int> arr;
cin >> test;
while (test--) {
cin >> n;
for (int i = 0; i < n; i++) {
cin >> a;
arr.push_back(a);
}
nth_element(arr.begin(), arr.begin() + 1, arr.end());
cout << *(arr.begin() + 1) << endl;
arr.clear();
}
return 0;
}
1.3.6 考试排名 （排序）
#include <iostream>
#include <cstdio>
#include <vector>
#include <algorithm>
using namespace std;
struct Rank {
char name[10];
int cnt;
int ti;
void clear() {
cnt = 0;
ti = 0;
}
};
vector<Rank> stu;
class cmp {
public:
bool operator() (const Rank &a, const Rank &b) const {
if (a.cnt > b.cnt) {
return true;
} else if (a.cnt == b.cnt) {
if (a.ti < b.ti) {
return true;
} else if (a.ti == b.ti) {
return strcmp(a.name, b.name) < 0;
}
return false;
}
return false;
}
};
int main() {
int n, m, a, b;
char str[10];
scanf("%d %d", &n, &m);
Rank current;
while (scanf("%s", current.name) != EOF) {
current.clear();
for (int j = 0; j < n; ++j) {
scanf("%s", str);
int num = sscanf(str, "%d(%d)", &a, &b);
if (num == 1) {
if (a > 0) {
current.cnt++;
current.ti += a;
}
} else {
current.cnt++;
current.ti += a + b * m;
}
}
stu.push_back(current);
}
sort(stu.begin(), stu.end(), cmp());
vector<Rank>::const_iterator pos;
for (pos = stu.begin(); pos != stu.end(); ++pos) {
printf("%-10s %2d %4d\n", pos->name, pos->cnt, pos->ti);
}
stu.clear();
return 0;
}
1.3.7 Saving HDU （贪心）
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
struct Treasure {
int per_money;
int volume;
Treasure(int a, int b) : per_money(a), volume(b) {}
};
class cmp {
public:
bool operator() (const Treasure &a, const Treasure &b) const {
return a.per_money > b.per_money;
}
};
vector<Treasure> tsure;
int main() {
int v, n, a, b;
while (cin >> v, v) {
cin >> n;
for (int i = 0; i < n; ++i) {
cin >> a >> b;
tsure.push_back(Treasure(a, b));
}
sort(tsure.begin(), tsure.end(), cmp());
vector<Treasure>::iterator pos;
int ret = 0;
for (pos = tsure.begin(); pos != tsure.end(); ++pos) {
if (v >= pos->volume) {
v -= pos->volume;
ret += pos->volume * pos->per_money;
} else {
ret += v * pos->per_money;
break;
}
}
cout << ret << endl;
tsure.clear();
}
return 0;
}
1.3.8 Wooden Sticks （贪心）
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
struct Wood {
int length;
int weight;
Wood(int a, int b) : length(a), weight(b) {}
bool friend operator <= (const Wood &a, const Wood &b) {
if (a.length <= b.length && a.weight <= b.weight) {
return true;
}
return false;
}
};
class cmp {
public:
bool operator() (const Wood &a, const Wood &b) const {
if (a.length < b.length) {
return true;
} else if (a.length == b.length) {
return a.weight < b.weight;
}
return false;
}
};
vector<Wood> wood;
vector<bool> hash;
int main() {
int test, n, a, b;
cin >> test;
while (test--) {
cin >> n;
hash.resize(n);
for (int i = 0; i < n; ++i) {
cin >> a >> b;
wood.push_back(Wood(a, b));
}
sort(wood.begin(), wood.end(), cmp());
int cnt = 0;
for (int i = 0; i < n; ++i) {
if (!hash[i]) {
Wood tmp = wood[i];
for (int j = i; j < n; ++j) {
if (!hash[j] && tmp <= wood[j]) {
tmp = wood[j];
hash[j] = true;
}
}
cnt++;
}
}
cout << cnt << endl;
wood.clear();
hash.clear();
}
return 0;
}
原创文章如转载请注明：转自￥忘%风 {http://www.cnblogs.com/slave_wc}
本文地址: ACM Steps Chapter One
{http://www.cnblogs.com/slave_wc/archive/2011/04/25/2026612.html }
