3.2 查找元素

题号	题目	分数
B1041	考试座位号	15
B1004	成绩排名	20
B1028	人口普查	20
B1032	挖掘机技术哪家强	20
A1011	World Cup Betting	20
A1006	Sign In and Sign Out	25
A1036	Boys vs Girls	25

B1041. 考试座位号

#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. 成绩排名

#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

注意点：写代码一定要认真！！！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区间内的情况，这时必须特判输出为0，否则会返回“格式错误”.

#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. 挖掘机技术哪家强

#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’}数组表示比赛结果比利用if/else来输出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;
}