[C++知识库]杭电OJ第一阶段简单操作:2000—2011、2039

2000 ASCII码排序

#include <iostream>
#include <algorithm>
using namespace std;

int main()
{
    char a, b, c;
    while (cin >> a >> b >> c) {
        char sum = a + b + c;
        char maxx = max(max(a,b),c);
        char minn = min(min(a,b),c);
        char mid = sum - maxx - minn;
        cout << minn << ' ' << mid  << ' ' << maxx << endl;
    }
    return 0;
}

#include <stdio.h>
#include <string.h>

int main()
{
    char a, b, c;
    while (scanf("%c %c %c",&a,&b,&c)!=EOF) {
        getchar();
        char t;
        if (a > b) {
            t = a;
            a = b;
            b = t;
        }
        if (a > c) {
            t = a;
            a = c;
            c = t;
        }
        if (b > c) {
            t = b;
            b = c;
            c = t;
        }
        printf("%c %c %c\n",a,b,c);
    }

    return 0;
}

2001 计算两点间的距离 sqrt(),pow() math.h

#include <stdio.h>
#include <math.h>

int main()
{
    double x1, x2, y1, y2;
    double sum = 0;
    while (scanf("%lf %lf %lf %lf",&x1,&y1,&x2,&y2)!=EOF) {
        sum = sqrt(pow(x1 - x2,2) + pow(y1 - y2,2));
        printf("%.2lf\n",sum);
    }

    return 0;
}

2002 计算球体积

#include <stdio.h>
#include <math.h>
#define PI 3.1415927
int main()
{
    double r;
    double are;
    while (scanf("%lf",&r)!=EOF) {
        are = (double)4/3 * PI * pow(r,3);
        printf("%.3lf\n",are);
    }
    return 0;
}

2003 求绝对值

#include <stdio.h>

int main(){
	double x;
	while ((scanf("%lf", &x))!= EOF)
		printf("%.2f\n", (x > 0) ? x : -x);
	return 0;
}

int,abs()函数在头文件“stdlib.h”中，浮点,fabs()函数在头文件“math.h”中
想试试c++行不行

#include <iostream>
#include <math.h>
using namespace std;

int main()
{
    double a;
    while (cin >> a) {
        printf("%.2f\n", fabs(a));
    }
    return 0;
}

2004 成绩转换

#include <iostream>
using namespace std;

int main()
{
    double t;
    while (cin >> t) {
        if (t >= 90 && t <= 100) {
            cout << 'A' << endl;
        } else if (t >= 80 && t <= 89) {
            cout << 'B' << endl;
        } else if (t >= 70 && t <= 79) {
            cout << 'C' << endl;
        } else if (t >= 60 && t <= 69) {
            cout << 'D' << endl;
        } else if (t >= 0 && t <= 59) {
            cout << 'E' << endl;
        } else {
            cout << "Score is error!" << endl;
        }
    }

    return 0;
}

2005 第几天？

#include <iostream>
using namespace std;

int main()
{
    int year, month, day;
    while (cin >> year >> month >> day) {
        int m[12] = {31,28,31,30,31,30,31,31,30,31,30,31};
        if ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0) {
            m[1] = 29;
        }
        int sum = 0;
        for (int i = 0; i < month - 1; ++i) {
            sum += m[i];
        }
        sum += day;
        cout << sum << endl;
    }
    return 0;
}

2006 求奇数的乘积

#include <iostream>
using namespace std;

int main()
{
    int n;
    int num;
    while (cin >> n) {
        int sum = 1;
        while (n--) {
            cin >> num;
            if (num % 2 != 0) {
                sum *= num;
            }
        }
        cout << sum << endl;
    }
    return 0;
}

2007 平方和与立方和
一直没找到哪里错输入的哪一个大是不确定的

#include <iostream>
#include <math.h>
using namespace std;

int main()
{
    int n, m;
    while (cin >> n >> m) {
        if (n > m) {
            int temp = m;
            m = n;
            n = temp;
        }
        int x = 0, y = 0;
        for (int i = n; i <= m; ++i) {
            if (i % 2 != 0) {
                y += (pow(i,3));
            } else {
                x += (i*i);
            }
        }
        cout << x << ' ' << y << endl;
    }
    return 0;
}

2008 数值统计

#include <iostream>
using namespace std;

int main()
{
    int n;
    while (cin >> n,n!=0) {//&&n
        int a = 0, b = 0, c = 0;
        while (n--) {
            double num;
            cin >> num;
            if (num < 0) {
                ++a;
            } else if (num > 0) {
                ++b;
            } else {
                ++c;
            }
        }
        cout << a << ' ' << c << ' ' << b << endl;
    }

    return 0;
}

2009 求数列的和

#include <iostream>
#include <math.h>
using namespace std;

int main()
{
    double m, n;
    while (cin >> m >> n) {
        double sum = 0;
        for (int i = 0; i < n; ++i) {
            sum += m;
            m = sqrt(m);
        }
        printf("%.2lf\n",sum);
    }
    return 0;
}

2010 水仙花数

#include <iostream>
#include <math.h>
using namespace std;

bool iswf(int num) {
    int a, b , c;
    a = num / 100;
    b = num / 10 % 10;
    c = num % 10;
    if (pow(a,3)+ pow(b,3) + pow(c,3) == num) {
        return true;
    }
    return false;
}
int main()
{
    int m, n;
    while (cin >> m >> n) {
        int flag = 1;
        for (int i = m; i <= n; ++i) {
            if (iswf(i)) {
                if (flag == 1) {//是第一个数据则直接输出
                    cout << i;
                } else {//不是第一个数据要先输出一个空格再输出结果
                    cout << ' ' << i;
                }
                flag = 0;
            }
        }
        if (flag == 0) {
            cout << endl;
        } else {
            cout << "no" << endl;
        }
    }
    return 0;
}

2011 多项式求和
单精度浮点数用f,双精度浮点数用lf(printf可混用，但scanf不能混用)

#include <iostream>
using namespace std;

int main()
{
    int n;
    cin >> n;
    while (n--) {
        int num;
        double sum = 0;
        cin >> num;
        for (int i = 1; i <= num; ++i) {
            if (i % 2 == 0) {
                sum -= 1.0/i;
            } else {
                sum += 1.0/i;
            }
        }
        printf("%.2lf\n",sum);
    }
    return 0;
}

2039 三角形

#include <iostream>
using namespace std;

int main()
{
    int m;
    cin >> m;
    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;
}