HDOJ入门刷题记录

 菜鸟的刷题记录

第一阶段 :   1000、1089—1096、1001

1000:A + B Problem

#include 
using namespace std;
int main(void)
{
    int a,b;
    while(scanf("%d%d",&a,&b) != EOF)
        cout << a + b << endl;
    return 0;
}

1001

#include 
using namespace std;
int main(void)
{
    int a,b;
    while(scanf("%d %d",&a,&b) == 2)
        cout << a + b << endl;
    return 0;
}

1089:Sum Problem

#include 
using namespace std;
int main(void)
{
    int n,sum;
    while(scanf("%d",&n) == 1)
    {
        sum = n / 2.0 * (n+1);
        cout << sum << endl << endl;
    }
    return 0;
}

1090:A+B for Input-Output Practice (II)

#include 
using namespace std;
int main(void)
{
    int n;
    cin >> n;
    int a,b;
    while (n-- && scanf("%d%d",&a,&b) == 2)
        cout << a + b << endl;
    return 0;
}

1091:A+B for Input-Output Practice (III)

#include 
using namespace std;
int main(void)
{
    int a,b;
    while(cin >> a >> b) {
        if (a == 0 && b == 0)
            return 0;
        cout << a + b << endl;
    }
    return 0;
}

1092:A+B for Input-Output Practice (IV)

#include 
using namespace std;
int main(void) {
    int n,sum,t;
    while(cin >> n && n != 0) {
        sum = 0;
        while (n--) {
            cin >> t;
            sum += t;
        }
        cout << sum << endl;
    }
    return 0;
}

1093

#include 
using namespace std;
int main(void)
{
    int n;
    cin >> n;
    while(n--)
    {
        int m,t,sum = 0;
        cin >> m;
        while (m-- && cin >> t)
            sum += t;
        cout << sum << endl;
    }
    return 0;
}

1094

#include 
using namespace std;
int main(void)
{
    int n,t,sum;
    while(cin >> n){
        sum = 0;
        while(n-- &&  cin >> t){
            sum += t;
            //cout << sum << endl;
        }
        cout << sum << endl;
    }
    return 0;
}

1095

#include 
using namespace std;
int main(void)
{
    int a,b;
    while(cin >> a >> b)
        cout << a + b << endl << endl;
    return 0;
}

1096

#include 
using namespace std;
int main(void)
{
    int n;
    cin >> n;
    while(n--)
    {
        int m,t,sum = 0;
        cin >> m;
        while (m-- && cin >> t)
            sum += t;
        cout << sum << endl;
        if(n != 0)
            cout << endl;
    }
    return 0;
}

第二阶段 :2000—2011、2039

2000:ASCII码排序

#include 
#include 
using namespace std;
const int n = 3;
int main(void)
{
	char c[n];
	while(cin >> c[0] >> c[1] >> c[2])
	{
		sort(c,c+n); 
		//打印输出 
		for(int i = 0;i < n;i++){
			if(i < n - 1 )
				cout << c[i] << " ";
			else
				cout << c[i] << endl;
		}
	}
	return 0;
}

2001:计算两点间的距离

#include 
#include 
#include
using namespace std;
int main(void)
{
	double x1,y1,x2,y2;
	while(cin >> x1 >> y1 >> x2 >> y2)
		printf("%.2f\n",sqrt((x2-x1)*(x2-x1) + (y2-y1)*(y2-y1)));
	return 0;
}

2002:计算球体积

#include 
#define PI 3.1415927
using namespace std;
int main(void)
{
	double r;
	while(cin >> r )
		printf("%.3f\n",4/3.0*PI*r*r*r);
	return 0;
}

2003:计算绝对值

#include 
using namespace std;
int main(void)
{
	double x;
	while(cin >> x)
		printf("%.2f\n",fabs(x));
}

2004:成绩分类

#include 
using namespace std;
int main(void)
{
	int score;
	while(cin >> score)
	{
		if(score >= 90 && score <= 100)
			cout << 'A' << endl;
		else if(score >= 80 && score < 90)
			cout << 'B' << endl;
		else if(score >= 70 && score < 80)
			cout << 'C' << endl;
		else if(score >= 60 && score < 70)
			cout << 'D' << endl;
		else if(score >= 0 && score < 60)
			cout << 'E' << endl;
		else if(score < 0 || score > 100)
			cout << "Score is error!" << endl;
	}
}

2005:计算天数

#include 
using namespace std;
int main(void)
{
	int daysOfMonth[13] = {0,31,28,31,30,31,30,31,31,30,31,30,31}; 
	int y,m,d;
	int days;
	while(scanf("%d/%d/%d",&y,&m,&d) == 3)
	{ 
		days = 0;
		if((y%400==0 || (y%4==0 && y%100!=0)) && m >=3)
			daysOfMonth[2]++; 
		if(m == 1){
			cout << d << endl;
			continue;
		}
		for(int i = 1;i < m;i++)
			days += daysOfMonth[i];	
		cout << days + d << endl;
		daysOfMonth[2] = 28; //reset 
	}
}

2006:求奇数的乘积

#include 
using namespace std;
int main(void)
{
	int m,t,ret;
	while(cin >> m)
	{
		ret = 1;
		for(int i = 0;i < m;i++)
		{
			cin >> t;
			if(t % 2 != 0)
			 	ret *= t;
		}
		cout << ret << endl; 
	} 
}

2007:

#include 
using namespace std;
int main(void)
{
	long long  n,m,x,y;
	while(cin >> n >> m)
	{
		x = y = 0;
        // tips:
		if(n > m)
		{
			int t = n;
			n = m;
			m = t;
		}
		for(int i = n;i <= m;i++)
		{
			if(i % 2 == 0)
				x += i*i;
			else 
				y += i*i*i;
		}
		cout << x << " " << y << endl;
	}
}

2008

#include 
using namespace std;
int main(void)
{
	int n;double t;
	int a,b,c;
	while(cin >> n && n != 0){
		a = b = c = 0;
		while(n-- && cin >> t){
			if(t < 0) a++;
			if(t == 0) b++;
			if(t > 0) c++;
		}
		cout << a  << " " << b << " " << c << endl;	
	}
	return 0;
}

2009:数值统计

#include 
using namespace std;
int main(void)
{
	double n,m,ret;
	while(cin >> n >> m)
	{
		ret = n;
		for(int i = 0;i < m - 1;++i)
		{
			n = sqrt(n);
			ret += n;
		}
		printf("%.2f\n",ret);
	}
	return 0;
}

2010:多项式求和 

#include 
using namespace std;
int main(void)
{
	double sum;
	int m,n; cin >> m;
	while(m-- && cin >> n)
	{	
		sum = 0;
		for(int i = 1;i <= n;i++)
		{ 
			if(i % 2 != 0) 
				sum += 1 * 1.0 / i;
			else
				sum -= 1 * 1.0 / i;
		}
		printf("%.2f\n",sum); 
	} 
}

2011:水仙花数

#include 
using namespace std;
int main(void)
{
	int m,n;
	while(cin >> m >> n)
	{
		int flag = 0;
		for(int i = m;i <= n;i++)
		{
			int x = 0,t = i;
			while(t > 0)
			{
				x += pow(t%10,3);
				t /= 10;
			}
			if(x == i) 
			{
				if(flag == 1)
					cout << " ";
				cout << i ;
				flag = 1; 
			}
		}
		if(flag == 1) cout << endl; 
		if(flag == 0) cout << "no" << endl;
	}
}

 

2039:三角形

#include 
using namespace std;
int main(void)
{
	int m;cin >> m;
	//题目没有说是整数...--! 
	double a,b,c;
	while(m--)
	{
		cin >> a >> b >> c;
		if(a + b > c && a + c > b && b + c > a )
			cout << "YES" << endl;
		else 
			cout << "NO" << endl;
	}
	return 0;
}

1970:

1062:Text Reverse

//使用了stl中的栈
#include
using namespace std;
int main(void)
{
    int n;
    cin >> n;
    getchar();
    char s[1050];
    while(n--)
    {
        gets(s);
        int len = strlen(s);
        stack  st;
        for(int i = 0; i < len; i++)
        {
            if(s[i] != ' ')
                st.push(s[i]);
            if(s[i] == ' ' || i == len - 1 )
            {
                while(! st.empty())
                {
                    cout << st.top();
                    st.pop();
                }
                if(s[i] == ' ')
                    cout << ' ';
            }
        }
        cout << endl;
    }
    return 0;
}

1720:

void p1720()
{
    int a,b;
    while(scanf("%x %x",&a,&b) != EOF)
        cout << a + b << endl;
}

2104:

void p2104()
{
    int n,m,t;
    while(cin >> n >> m)
    {
        if(n == -1 && m == -1) break;
        while(m != n)
        {
            t = m;
            m = n % m;
            n = t;
        }
        if(n == 1)
            cout << "YES" << endl;
        else cout << "POOR Haha" << endl;
    }
}

1064:

void p1064()
{
    double income;
    double sum = 0;
    for(int i = 0;i < 12;i++)
	{
        cin >> income;
        sum += income;
	}
	double average = sum / 12;
    printf("$%.2f",average);
}

2734:

#include 
using namespace std;
int main(void) {
    char s[256];
    int sum;
    while (gets(s) && s[0] != '#') {
        int len = strlen(s);
        sum = 0;
        for (int i = 0; i < len; i++) {
            if (s[i] == ' ')
                continue;
            else
                sum += (i + 1) * (s[i] - 'A' + 1);
        }
        cout << sum << endl;
    }
}

2012

#include
using namespace std;
bool isPrime(int x)
{
	if(x < 2) return false;
	if(x % 2 == 0 && x != 2) 
		return false;
	for(int i = 2;i*i < x;i++)
		if(x % i == 0) return false;
	return true;
}
int main(void)
{
	int x,y;
	while(cin >> x >> y)
	{
		int flag = 1;
		if(x == 0 && y == 0)
			return 0;
		else
			for(int i = x;i <= y;i++)
				if(!isPrime(i*i+i+41))
					flag = 0;
		if(flag == 1) cout << "OK" << endl;
		if(flag == 0) cout << "Sorry" << endl; 
	}
	return 0;
}

2103

#include
using namespace std;
int main(void)
{
	int n;
	while(cin >> n)
	{
		int total = 1;
		for(int i = n-1;i >= 1;i--)
			 total = 2*(total+1); 
		cout << total << endl; 
	} 
	return 0;
}

2104

#include
using namespace std;
int main(void)
{
	int n;
	while(cin >> n)
	{
		int a[n],sum = 0;double average;
		for(int i = 0;i < n;i++)
		{
			cin >> a[i];
			sum += a[i];
		}
		int *maxN = max_element(a,a+n); 
		int *minN = min_element(a,a+n);
		sum -= (*maxN + *minN); 
		average = sum * 1.0 / (n-2);
		printf("%.2f\n",average); 
	}	
} 

2015

#include
#include
using namespace std;
int main(void)
{
	int n,m;
	while(cin >> n >> m)
	{
		int sum = 0,average = 0,cnt = 0;
		for(int i = 2;i <= 2*n;i+=2){
			sum = sum + i;
			if(i/2 % m == 0){
				average = sum / m;
				if(cnt != 0)
					cout << " " <<  average;
				else {
					cnt++;
					cout << average;
				}
				sum = 0;
			}
		}
		if(n % m == 0) cout << endl;
		else cout << " "<< sum / (n % m) << endl;
	}
	return 0;	
} 

2016

#include
using namespace std;
int main(void)
{
	int n;
	int a[100] = {0};
	while(cin >> n && n != 0)
	{
		for(int i = 0; i < n;i++)
			cin >> a[i];	
		int minN = 0;
		//不用stl找最小值的下标 
		for(int i = 1;i < n;i++)
		{
			if(a[i] < a[minN])
				minN = i; 
		}
		int t = a[0];
		a[0] = a[minN];
		a[minN] = t; 
		//输出
		for(int i = 0;i < n - 1;i++) 
			cout << a[i] << " ";
		cout << a[n-1] << endl; 	 
	}
	return 0;
}

2017

#include
#include
using namespace std;
int main(void)
{
	int n;cin>>n;
	getchar(); //读取前一个cin留在缓冲区的回车  
	string s;
	while(n--)
	{
		string s;
		getline(cin,s);
		int len = s.length(),cnt = 0;
		for(int i = 0;i < len;i++)
			if(s[i] >= '0' && s[i] <= '9')
				cnt++; 
		cout << cnt << endl; 
	}
	return 0;	
} 

2018

#include
using namespace std;
int main(void)
{
	int f[50]; int n;
	while(cin >> n && n != 0)
	{
		f[1] = 1;f[2] = 2;f[3] = 3;
		for(int i = 4;i <=n;i++)
		{
			f[i] = f[i-3] + f[i-1];	
		}
		cout << f[n] << endl;
	}
	return 0;
} 

2019

#include
using namespace std;
int main(void)
{
	int n,m,x;
	while(cin >> n >> m && n != 0 && m != 0)
	{
		//online 
		int t,cnt = 0; 
		for(int i = 0;i < n;i++) 
		{
			cin >> t;
			if(t < m )
				cout << t << " ";
			//one time 
			else if(t >= m ) 
			{
				if(cnt == 0) { 
					cnt ++;
					cout << m << " " << t;
				} 
				else
					cout << " " << t;
			}  
		}
		//last loc 
		if(m > t)
			cout << m << endl;
		else 
			cout << endl; 
	}
	return 0;
} 

2020

#include 
using namespace std;
const int MAX_N = 100;
int n, a[MAX_N];
void solve()
{
	while(cin >> n && n != 0)
	{
		for(int i = 0;i < n;i++)
			scanf("%d",&a[i]);
		//bubble sort
		for(int i = n - 1;i >= 0;i--){
			for(int j = 0;j < i;j++){
				if(fabs(a[j]) < fabs(a[j+1]))
					swap(a[j],a[j+1]);
			}
		}
		//输出 
		for(int i = 0;i < n-1;i++)
			printf("%d ",a[i]);
		printf("%d\n",a[n-1]);
	}
}

2021

#include
#include
using namespace std;
const int money[6] = {100,50,10,5,2,1}; 
int n,t,x;
void solve()
{
	while(cin >> n && n != 0)
	{
		x = 0;
		for(int i = 0;i < n;i++){
			cin >> t;
			for(int j = 0;j < 6;j++)
			{
				x += t / money[j];
				t %= money[j]; 
			} 
		}
		cout << x << endl; 			
	}	
}