C语言第二章部分习题代码

阳光穿透心脏的1/2处 2022-05-08 10:24 187阅读 0赞

#include "TypeExpression.h"
    
    
    TypeExpression::TypeExpression(void)
    {
    }
    
    
    TypeExpression::~TypeExpression(void)
    {
    }
    
    /*
    * 十六进制转换十进制
    */
    void htoi(char s[]);
    void practice2_3();
    void squeeze(char retrieval[], char cha[]);
    void practice2_4();
    int any(char s1[], char s2[]);
    void practice2_5();
    unsigned getbits(unsigned x,int p, int n);
    void setbits(unsigned x, int p, int n, unsigned y);
    void practice2_6();
    void invert(unsigned x, int p, int n);
    void practice2_7();
    void rightrot(unsigned int x, int n);
    void practice2_8();
    int bitcount(unsigned x);
    void main()
    {
    	practice2_8();
    	printf("结束打印");
    }
    
    void htoi(char s[]){
    	int totalNum = 0;
    	int c;
    	int position = 0;
    	c = s[position];
    	if (s[0] == '0' && s[1] == 'x' || s[1] == 'X') {
    		while (c != '\0' && c > 0) {
    			position ++;
    			c = s[position];
    		}
    		position --;
    		for (c = s[position]; position > 1; position --) {
    			int num;
    			// 小写转大写
    			if (c >= 'a' && c <= 'z') {
    				c -= 'a' - 'A';
    			}
    			// 大写A～F转换成10-15,数字字符转数字0-9
    			if (c >= 'A' && c <= 'F') {
    				num = c - 'A' + 10;
    			} else {
    				num = c - '0';
    			}
    			if (position > 2) {
    				int exponent = position - 2; // 指数
    				int exponentNum = 1; // 十六进制对应指数结果值
    				for (; exponent > 0; exponent--)
    				{
    					exponentNum *= 16;
    				}
    				num *= exponentNum; // 计算当前位置对应的结果值
    			}
    			totalNum += num;
    		}
    		printf("\n十六进制转换十进制\t%6d", totalNum);
    	} else {
    		printf("\n字符串不符合十六进制格式");
    	}
    	
    	printf("\n打印结束");
    }
    
    void practice2_3() {
    	printf("录入合法的十六进制的字符串，将帮您转换成对应的十进制数\n");
    	int c;
    	char ch [500];
    	int position = 0;
    	while ((c = getchar()) != EOF && c != '\n' && c != '\t' && c != ' ') {
    		ch[position] = c;
    		position ++;
    	}
    	htoi(ch);
    }
    
    void squeeze(char retrieval[], char cha[]) {
    	char retrievalRequest[200];
    	int i = 0;
    	int retrievalRequestIndex = 0;
    	int c;
    	while (i < 200 && (c = cha[i]) != '\0' && c >= 0)
    	{
    		bool isContainer = false;
    		int j = 0;
    		int rc;
    		while ((rc = retrieval[j ++]) != '\0' && rc >= 0) {
    			if(rc == c) {
    				isContainer = true;
    				break;
    			}
    		}
    		if (!isContainer) {
    			retrievalRequest[retrievalRequestIndex ++] = c;
    		}
    		i ++;
    	}
    	retrievalRequest[retrievalRequestIndex] = '\0';
    	printf("\n需要去除敏感字符为：\t%s", retrieval);
    	printf("\n去除后的结果\t%s", retrievalRequest);
    }
    
    char retrieval[6] = {'c', 'h', 'l', 'w', 'y', '\0'};
    void practice2_4(){
    	printf("您输入的字符串将进行敏感字符过滤\n");
    	char scannCha[200];
    	int c;
    	int index = 0;
    	while(index < 200 &&(c = getchar()) != EOF && c != '\n'){
    		scannCha[index++] = c;
    	}
    	
    	squeeze(retrieval, scannCha);
    }
    
    int any(char s1[], char s2[]){
    	char c1;
    	char c2;
    	int i = 0;
    
    	while ((c2 = s2[i]) != EOF && c2 != '\0')
    	{
    		int j = 0;
    		while ((c1 = s1[j++]) != EOF && c1 != '\0')
    		{
    			if (c1 == c2)
    				return i;
    		}
    		i++;
    	}
    	return -1;
    }
    #define CHAR_MAX 200
    void practice2_5() {
    	printf("请输入任意字符\n");
    	char s1[CHAR_MAX];
    	int c;
    	int index = 0;
    	while(index < CHAR_MAX && (c = getchar()) != EOF && c != '\n'){
    		s1 [index++] = c;
    	}
    	s1[index] = '\0';
    	printf("查找字符串：%s 任意字符在字符串：%s,中第一次出现的位置,如果不存在则返回 -1",s1, retrieval);
    	int retrievalIndex = any(s1, retrieval);
    	if (retrievalIndex > -1) {
    		printf("\n第一次出现的字符为%s,出现的位置%3d", retrieval[retrievalIndex], retrievalIndex);
    	} else {
    		printf("\n没有相同的字符");
    	}
    	
    }
    
    unsigned getbits(unsigned x, int p, int n){
    	int a = x >> (p - n);
    	printf("\n对%d右移%d位 结果%d", x, (p -n), a);
    	int b = ~(~0 << n);
    	printf("\n用于按位与的值%d", b);
    	int c = a & b;
    	printf("\nrequest= %d", c);
    	return c;
    }
    
    void setbits(unsigned x, int p ,int n, unsigned y) {
    	unsigned int a = getbits(x, p, n);
    	int b = y >> n << n;
    	int request = b + a;
    	printf("\n将%d中最右边的%d位置设置为%d结果 %d", y, n, a, request);
    }
    
    void practice2_6(){
    	setbits(77, 4, 3, 1000);
    }
    
    void invert(unsigned x, int p, int n){
    	printf("\n将%d中从%d位置开始向%d位置的(二进制)求反，其余位置不变", x, p, n);
    	int interval = getbits(x, p, n);
    	int rest = x & ~(~0 << (p - n));
    	printf("\n剩余位数的值rest= %d", rest);
    	int unInterval = ~ interval ^ (~0 << n);// 11111001 ^ 11111000 = 1
    	printf("\n对区间内的值%d取反，与对~0向左移%d位的结果求按位异或结果unInterval= %d", interval, n, unInterval);
    	int andRest = unInterval<< (p-n) | rest;
    	printf("\n取反后的值与剩余的值按位或【|】andRest= %d", andRest);
    	int value = x >> p << p | andRest;
    	printf("\n对原始值先左后右移动 %d 位，再与andRest求按位或【|】打印结果值value= %d", p ,value);
    }
    
    void practice2_7(){
    	invert(80, 4, 3);
    }
    
    void rightrot(unsigned int x, int n) {
    	int x1 = x;
    	int p;
    	for (p = 0; x != 0; x>>=1)
    	{
    		p++;
    	}
    	printf("\n%d的二进制位数 %d", x ,p);
    	n = n > p ? p :n;
    	int move = x & ~(~0 << n);
    	printf("\n%d右移%d位移出的值 = %d", x, n, move);
    	int moveLeft = move << (p - n); // 待移动位置左移
    	printf("\n%d左移%d位移出的值 = %d", move, p - n, moveLeft);
    	int rest = x >> n;
    	printf("\n%d右移%d位 = %d", x, n, rest);
    	int request = rest | moveLeft;
    	printf("\n%d右移%d位并补充到前面得到值 = %d", x, n, request);
    }
    
    void practice2_8() 
    {
    	rightrot(77, 4);
    }
    
    int bitcount(unsigned x)
    {
    	int b;
    	for (b = 0; x != 0; x>>=1)
    	{
    		if(x > x & 01)
    			b++;
    	}
    	return b;
    }