山东大学23强基班计算机导论第四次习题答案

T7.1

#include <iostream>
using namespace std;

int main()
{
    int lower,upper;
    cin>>lower>>upper;
    if(lower > upper || upper > 100 || lower <=0)
    {
        cout<<"Invalid.";
        return 0;
    }
    cout<<"fahr celsius"<<endl;
    for(int i = lower;i<=upper;i+=2)
    {
        printf("%d%6.1lf\n",i, 5.0 * (i - 32.0)/9.0);
    }
}

T7.2

#include <iostream>
using namespace std;

int main()
{
    int N;
    cin>> N;
    double sum = 0;
    for(int i = 1; i<= N; i++)
        sum+= 1.0 / i;
    printf("sum = %.6lf",sum);
}

T7.3

#include <iostream>
using namespace std;

int main()
{
    int N;
    cin >> N;
    double sum = 0;
    for(int i = 1; i<= N*2 ; i += 2)
        sum += 1.0 / i;
    printf("sum = %.6lf",sum);
}

T7.4

#include <iostream>
using namespace std;

int main()
{
    int N;
    cin>> N;
    double sum = 0;
    for(int i = 1; i <= N ; i++)
    {
        if( (i & 1) == 1)
            sum += (1.0 / (i * 3 -2));
        else
            sum -= (1.0 / (i * 3 -2));
    }
    printf("sum = %.3lf",sum);
}

T7.5

#include <iostream>
using namespace std;

int main()
{
    int m,n;
    cin>>m>>n;
    double sum =0;
    for(int i=m;i<=n;i++)
    {
        sum += i*i + 1.0/i;
    }
    printf("sum = %.6lf",sum);
}

T7.6

#include <iostream>
using namespace std;

int main()
{
    int N;
    cin >> N;
    double sum = 0;
    for(int i = 1;i<=N;i++)
    {
        if ( (i & 1) == 1)
            sum += i / ( 2*i -1.0);
        else
            sum -= i / ( 2 *i -1.0);
    }
    printf("%.3lf",sum);
}

T7.7

#include <iostream>
using namespace std;

int main()
{
    double esp;
    cin>> esp;
    int cur = 1;
    double sum =0;
    do{
        if( (cur & 1) == 1)
            sum+=1.0/(cur * 3.0 -2.0);
        else
            sum-=1.0/(cur * 3.0 -2.0);
        cur++;
    } while(1.0/(cur * 3.0 -2.0) >= esp);
    
    printf("sum = %.6lf",sum);
}

T7.8

#include <iostream>
using namespace std;

int main()
{
    int a,N;
    cin>>a>>N;
    int count = 0;
    while(N--)
    {
        count ++;
        int n;
        cin>>n;
        if(n < 0)
            break;
        
        if(n > a)
            cout<<"Too big"<<endl;
        else if(n<a)
            cout<<"Too small"<<endl;
        else
        {
            if(count == 1)
                cout<<"Bingo!"<<endl;
            else if(count <=3)
                cout<<"Lucky You!"<<endl;
            else
                cout<<"Good Guess!"<<endl;
            return 0;
        }
    }
    cout<<"Game Over"<<endl;
}

T7.9

#include <iostream>
using namespace std;

int main()
{
    int n;
    cin>>n;
    double sum =1 ;
    double gamma = 1;
    for(int i = 1;i <=n ; i++)
    {
        gamma *= i;
        sum += 1.0 / gamma;
    }
    printf("%.8lf",sum);
}

T7.10

#include <iostream>
using namespace std;

int main()
{
    int n;
    cin>>n;
    int minn;
    cin>>minn;
    while(--n)
    {
        int num;
        cin>>num;
        minn = min(minn,num);
    }
    cout<<"min = "<<minn;
}