1-10

1、

 

 分析：

素数的概念：素数又叫质数。素数，指的是“大于1的整数中，只能被1和这个数本身整除的数”。

合数的概念：大于1的整数中，除了1和自身外，还能被其他正整数整除的数。也可表述为：在大于1的整数中，除了1和自身两个约数外，还有其他约数的正整数。

# include <stdio.h>
# include <math.h>
int isPrime(int num) {
    //素数：大于1，除了1和本身，无其他因子
    //合数：大于1，除了1和本身，还有其他因子
    if (num == 1) {
        return 0;
    }
    else {
        int m = sqrt(num);
        for (int i = 2; i <= m; i++) {
            if (num % m == 0) {
                return 0;//合数
            }
        }
        return 1;//质数
    }
        
}
int main() {
    int num = 0;
    scanf_s("%d", &num);
    while (num != -1) {
        int ret = isPrime(num);
        if (ret == 1) {
            printf("is prime\n");
        }
        else {
            printf("no\n");
        }
        scanf_s("%d", &num);
    }
    return 0;
}

2、

 

 代码：

# include <stdio.h>
/// <summary>
/// 把当前num的各位数组存放到数组bArr中，并存放位数
/// </summary>
/// <param name="num"></param>
/// <param name="bArr"></param>
/// <param name="bArrLen"></param>
void getPerBite4(int num,int bArr[],int *bArrLen) {
    while (num>0)
    {
        bArr[*bArr] = num % 10;
        *bArrLen +=1;//这里不能使用++,使用++就是指针的递增
        num /= 10;
    }
}

/// <summary>
/// 求x的y次方
/// </summary>
/// <param name=""></param>
/// <param name=""></param>
/// <returns></returns>
int pow(x, y) {
    int mul = 1;
    for (int i = 1; i <= y; i++) {
        mul *= x;
    }
    return mul;
}

/// <summary>
/// 判断是不是水仙数
/// </summary>
/// <param name="num"></param>
/// <param name="bArr"></param>
/// <param name="bArrLen"></param>
void isNarNum(int num, int bArr[], int bArrLen) {
    int sum = 0;
    for (int i = 0; i < bArrLen; i++) {
        sum += pow(bArr[i], bArrLen);
    }
    if (sum == num) {
        printf("%d\n", num);
    }
}

int main() {
    for (int i = 1; i <= 2000; i++) {
        int bArr[10] = { 0 };
        int bArrLen = 0;
        getPerBite4(i, bArr, &bArrLen);
        isNarNum(i, bArr, bArrLen);
    }
    return 0;
}

结果：

3、

 代码：

# include <stdio.h>

void isPerfectNum(int num) {
    int sum = 0;
    for (int i = 1; i < num; i++) {
        if (num % i == 0) {
            sum += i;
        }
    }
    if (sum == num) {
        printf("%d\n", num);
    }
}


int main() {
    for (int i = 2; i <= 2000; i++) {
        isPerfectNum(i);
    }
    return 0;
}

结果：

 

4、

代码：

# include <stdio.h>
/// <summary>
/// 最小公倍数=乘积/最大公约数
/// 最大公约数用辗转相除法求得
/// </summary>
/// <param name="num1"></param>
/// <param name="num2"></param>
/// <returns></returns>
int getLowestComMul(int num1, int num2) {//初始时,num1>=num2
    int mulNum = num1 * num2;
    int mod=1;
    while (mod != 0) {
        mod = num1 % num2;
        num1 = num2;
        num2 = mod;
    }//执行完毕时,num1就是最大公约数
    return mulNum / num1;
}

int main() {
    int n, m;
    scanf_s("%d%d", &n, &m);
    while (n!=-1 && m!=-1)
    {
        if (n < m) {
            int temp = n;
            n = m;
            m = temp;
        }
        printf("%d\n",getLowestComMul(n, m));
        scanf_s("%d%d", &n, &m);
    }
    return 0;
}

结果：

 

5、

 代码：

# include <stdio.h>

int main() {
    double distance = 0;
    double height = 10.0;
    double boundHeight = height / 2;
    while (boundHeight > 0) {
        distance += 2 * boundHeight;
        boundHeight /= 2;
    }
    distance += height;
    printf("%f", distance);
    return 0;
}

结果：

 

 6、

 代码：

# include <stdio.h>
/// <summary>
/// 斐波那契数列
/// </summary>
/// <returns></returns>

int main() {
    int i, a, b, c, n;
    a = 1;
    b = 1;   /* 前两项已知为1，直接输出  */
    printf("输入前n项（n）：");
    scanf_s("%d", &n);      /* 输入需要输出到前几项  */
    printf("%d\n%d\n", a, b);    /* 先输出前两项     */
    for (i = 2; i < n; i++)      /* 因为输出了前两项  所以直接从第三项开始循环输出  */
    {
        c = a + b;   /* 前两项相加   */
        printf("%d\t", c);
        a = b;
        b = c;
    }
    return 0;
}

结果：

7、

 代码：

# include <stdio.h>

/// 判断一行字符串中除了冠词A外有多少单词

/// <summary>
/// 判断字符串是否是单词
/// (1)长度为1 （2）是字符a或A
/// </summary>
/// <param name="str"></param>
/// <returns></returns>
int isWord(char* pWord, int lenWord) {
    if (lenWord == 1 && (*pWord == 'A' || *pWord == 'a')) {
        return 0;
    }
    return 1;
}

/// <summary>
/// 遍历字符串，返回其中的单词个数
/// 先以空格为分隔符把每个“单词”分割开来，然后判定是不是真正的单词
/// </summary>
/// <param name="str"></param>
/// <returns></returns>
int wordCount(char* str) {
    int wNum = 0;
    while (*str!='\0')
    {
        char wordArr[10] = { 0 };
        int wordLen = 0;
        //str!='\0'目的：防止把最后一个字符串末尾的结束符计入计算
        while (*str!='\0' && *str!=' ')
        {
            wordArr[wordLen] = *str;
            wordLen++;
            str++;
        }
        int ret = isWord(wordArr, wordLen);
        if (ret == 1)
            wNum++;
        //当前遍历完一个单词,指向空格
        while (*str != '\0' && *str == ' ')
            str++;
    }
    return wNum;
}

int main() {
    char sentence[1000];
    gets(sentence);
    printf("%s\n", sentence);
    int wNum = wordCount(sentence);
    printf("%d\n", wNum);
    return 0;
}

结果：

8、

 代码：

# include <stdio.h>
/// <summary>
/// 握手问题
/// </summary>
/// <param name="team1"></param>
/// <param name="team2"></param>
void getSchedule(char team1[], char team2[]) {
    for (int i = 0; i < 3; i++) {
        for (int j = 0; j < 3; j++) {
            if (team1[i] == 'a' && team2[j] == 'd')
                continue;
            else if (team1[i] == 'c' && (team2[j] == 'd' || team2[j] == 'f'))
                continue;
            else
                printf("%c\t%c\n", team1[i], team2[j]);
        }
    }
}
int main() {
    char team1[] = {'a','b','c'};
    char team2[] = {'d','e','f'};
    getSchedule(team1, team2);
    return 0;
}

 结果：

9、

 代码：

#pragma warning(disable:4996)
#pragma warning(disable:6031)
#include <stdio.h>
#include <string.h>
/// <summary>
/// 字符串交换
/// </summary>
/// <param name="str1"></param>
/// <param name="str2"></param>
void strSwap(char* str1, char* str2) {
    char strTemp[100];
    strcpy(strTemp, str1);
    strcpy(str1, str2);
    strcpy(str2, strTemp);
}

/// <summary>
/// 3个字符串比较
/// 思想：ab比较，确定小和大；ac比较确定小和大；bc比较确定小和大
/// </summary>
/// <param name="strLow"></param>
/// <param name="strMid"></param>
/// <param name="strHigh"></param>
void strSort(char* strLow, char* strMid, char* strHigh) {
    char strTemp[100];
    if (strcmp(strLow, strMid) > 0)
        strSwap(strLow, strMid);
    if (strcmp(strLow, strHigh) > 0)
        strSwap(strLow, strHigh);
    if (strcmp(strMid, strHigh) > 0)
        strSwap(strMid, strHigh);
    
}

int main() {
    
    char strLow[100];
    char strMid[100];
    char strHigh[100];
    scanf("%s", strLow);
    scanf("%s", strMid);
    scanf("%s", strHigh);
    strSort(strLow, strMid, strHigh);
    printf("%s\t%s\t%s\n", strLow, strMid, strHigh);
    return 0;
}

结果：

10、

 代码：

#pragma warning(disable:4996)
#pragma warning(disable:6031)
#include <stdio.h>
#include <string.h>

void countFun(char* wordArr, int wordLen) {
    int cLetter=0;
    int cUpper=0;
    int cNum=0;
    int cTab=0;
    int cOther = 0;
    for (int i = 0; i < wordLen; i++) {
        if (wordArr[i] >= 'a' && wordArr[i] <= 'z')
            cLetter++;
        else if (wordArr[i] >= 'A' && wordArr[i] <= 'Z')
            cUpper++;
        else if (wordArr[i] >= '0' && wordArr[i] <= '9')
            cNum++;
        else if (wordArr[i] == ' ')
            cTab++;
        else
            cOther++;
    }
    printf("%d\t%d\t%d\t%d\t%d\n", cLetter, cUpper, cNum, cTab, cOther);
}

void countCharIn(char* str) {
    while (*str != '\0') {
        char wordArr[10] = { 0 };
        int wordLen = 0;
        while (*str != '\0' && *str != '\n') {
            wordArr[wordLen] = *str;
            wordLen++;
            str++;
        }
        countFun(wordArr, wordLen);
        while (*str != '\0' && *str == '\n')
            str++;
    }
    
}
int main() {
    char senten[100] = { "abc123 \n1098jk .[\n \n" };
    printf("%s\n", senten);
    printf("小写\t大写\t数字\t空格\t其他\n");
    countCharIn(senten);
    return 0;
}

结果：