3.2 查找元素

題號	題目	分數
B1041	考試座位號	15
B1004	成績排名	20
B1028	人口普查	20
B1032	挖掘機技術哪家強	20
A1011	World Cup Betting	20
A1006	Sign In and Sign Out	25
A1036	Boys vs Girls	25

B1041. 考試座位號

#include <cstdio>
const int MAXN = 1010;

typedef struct Student
{
    long long id;
    int examSeat;
}Student;

int main()
{
    int n, seat, examSeat;
    long long id;
    Student testSeat[MAXN];

    scanf("%d", &n);
    for(int i = 0; i < n; ++i)
    {
        scanf("%lld %d %d", &id, &seat, &examSeat);
        testSeat[seat].id = id;
        testSeat[seat].examSeat = examSeat;
    }

    int m;
    scanf("%d", &m);
    for(int i = 0; i < m; ++i)
    {
        scanf("%d", &seat);
        printf("%lld %d\n", testSeat[seat].id, testSeat[seat].examSeat);
    }

    return 0;
}

B1004. 成績排名

#include <cstdio>

struct Student
{
    char name[15];
    char id[15];
    int score;
}tmp, ansMax, ansMin;

int main()
{
    int n;
    ansMax.score = -1;
    ansMin.score = 101;
    scanf("%d", &n);
    for(int i = 0; i < n; ++i)
    {
        scanf("%s %s %d", tmp.name, tmp.id, &tmp.score);
        if(tmp.score > ansMax.score)
            ansMax = tmp;
        if(tmp.score < ansMin.score)
            ansMin = tmp;
    }
    printf("%s %s\n", ansMax.name, ansMax.id);
    printf("%s %s\n", ansMin.name, ansMin.id);
    return 0;
}

B1028. 人口普查

注意點：寫代碼一定要認真！！！oldest和youngest不要搞混，oldest的出生日期更小，youngest的出生日期更大。

有可能存在所有人的日期都不在合法區間內的情況，這時必須特判輸出爲0，否則會返回“格式錯誤”.

#include <cstdio>
struct Person
{
    char name[10];
    int yy, mm, dd;
}left, right, youngest, oldest;

void init()
{
    youngest.yy = left.yy = 1814;
    oldest.yy = right.yy = 2014;
    oldest.mm = youngest.mm = left.mm = right.mm = 9;
    oldest.dd = youngest.dd = left.dd = right.dd = 6;
}

bool lessEqu(Person a, Person b)
{
    if(a.yy != b.yy)
        return a.yy <= b.yy;
    else if(a.mm != b.mm)
        return a.mm <= b.mm;
    else
        return a.dd <= b.dd;
}

bool moreEqu(Person a, Person b)
{
    if(a.yy != b.yy)
        return a.yy >= b.yy;
    else if(a.mm != b.mm)
        return a.mm >= b.mm;
    else
        return a.dd >= b.dd;
}



int main()
{
    init();
    int n;
    scanf("%d", &n);

    Person tmp;
    int num = 0;
    for(int i = 0; i < n; ++i)
    {
        scanf("%s", tmp.name);
        scanf("%d/%d/%d", &tmp.yy, &tmp.mm, &tmp.dd);
        if(lessEqu(tmp, right) && moreEqu(tmp, left))
        {
            num += 1;
            if(lessEqu(tmp, oldest))
                oldest = tmp;
            if(moreEqu(tmp, youngest))
                youngest = tmp;
        }
    }

    if(0 == num)
        printf("0\n");
    else
        printf("%d %s %s", num, oldest.name, youngest.name);
    return 0;
}

B1032. 挖掘機技術哪家強

#include <cstdio>

const int MAXN = 100010;
int school[MAXN];

int main()
{
    int n;
    scanf("%d", &n);

    int id, score;
    for(int i = 0; i < n; ++i)
    {
        scanf("%d %d", &id, &score);
        school[id] += score;
    }

    int maxScore = -1;
    int k;
    for(int i = 1; i < MAXN; ++i)
    {
        if(school[i] > maxScore)
        {
            k = i;
            maxScore = school[i];
        }
    }

    printf("%d %d", k, maxScore);
    return 0;
}

A1011. World Cup Betting

注意：用char s = {‘W’, ‘T’, ‘L’}數組表示比賽結果比利用if/else來輸出W/T/L更方便。

#include <cstdio>

char s[3] = {'W', 'T', 'L'};

int main()
{
    double ans = 1.0, max1;
    int maxID;
    double tmp;

    for(int i = 0; i < 3; ++i)
    {
        max1 = -1;
        for(int j = 0; j < 3; ++j)
        {
            scanf("%lf", &tmp);
            if(tmp > max1)
            {
                max1 = tmp;
                maxID = j;
            }
        }
        printf("%c ", s[maxID]);
        ans *= max1;
    }
    printf("%.2f", (ans * 0.65 - 1) * 2);
    return 0;
}

A1006. Sign In and Sign Out

#include <cstdio>

struct Student
{
    char id[16];
    int hh, mm, ss;
}signIn, signOut, tmp;

void init()
{
    signIn.hh = 24;
    signIn.mm = signIn.ss = 60;
    signOut.hh = signOut.mm = signOut.ss = 0;
}

bool great(Student a, Student b)
{
    if(a.hh != b.hh)
        return a.hh >= b.hh;
    else if(a.mm != b.mm)
        return a.mm >= b.mm;
    return a.ss >= b.ss;
}

int main()
{
    init();
    int n;
    scanf("%d", &n);

    for(int i = 0; i < n; ++i)
    {
        scanf("%s %d:%d:%d", tmp.id, &tmp.hh, &tmp.mm, &tmp.ss);
        if(great(signIn, tmp))
            signIn = tmp;

        scanf("%d:%d:%d", &tmp.hh, &tmp.mm, &tmp.ss);
        if(great(tmp, signOut))
            signOut = tmp;
    }
    printf("%s %s", signIn.id, signOut.id);
    return 0;
}

A1036. Boys vs Girls

#include <cstdio>

struct Student
{
    char name[11];
    char gender;
    char id[11];
    int grade;
}M, F, tmp;

void init()
{
    M.grade = 101;
    M.gender = 'M';
    F.gender = 'F';
    F.grade = -1;
}

int main()
{
    init();
    int n;
    scanf("%d", &n);

    for(int i = 0; i < n; ++i)
    {
        scanf("%s %c %s %d", tmp.name, &tmp.gender, tmp.id, &tmp.grade);
        if('M' == tmp.gender && tmp.grade < M.grade)
            M = tmp;
        if('F' == tmp.gender && tmp.grade > F.grade)
            F = tmp;
    }

    if(F.grade == -1)
        printf("Absent\n");
    else
        printf("%s %s\n", F.name, F.id);

    if(M.grade == 101)
        printf("Absent\n");
    else
        printf("%s %s\n", M.name, M.id);

    if(F.grade != -1 && M.grade != 101)
        printf("%d", F.grade - M.grade);
    else
        printf("NA");
    return 0;
}