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1、实现 mystrcpy(), mystrcmp(), mystrcat(), mystrlen() ;
#define _CRT_SECURE_NO_WARNINGS#include#include size_t mystrlen(char c[]) { int i = 0; while (c[i]) { i++; } //i--; return i;}int mystrcmp(const char* str1, const char* str2) { int i = 0; while (str1[i] && str2[i]) { if (str1[i] == str2[i]) { i++; } else if (str1[i] > str2[i]) { return 1; } else { return -1; } } return 0;}char* mystrcpy(char* to, const char* from) { int i = 0; while (from[i]) { to[i] = from[i]; i++; } to[i] = from[i]; return to;}char* mystrcat(char* str1, const char* str2) { int i = 0; int len = strlen(str1); while (str2[i]) { str1[len] = str2[i]; i++; len++; } str1[len] = 0; return str1;}int main() { char c[50]; char a[50]; char* p,* sp; size_t len,standard_len; while (gets(c) != NULL) { len = mystrlen(c); standard_len = strlen(c); printf("字符串str的长度为：%d\n", len); printf("调用标准函数字符串str的长度为：%d\n", standard_len); printf("请输入另一个比较的字符串：\n"); gets(a); printf("调用mystrcmp函数的结果为：%d\n", mystrcmp(c, a)); printf("调用strcmp函数的结果为：%d\n", strcmp(c, a)); p = mystrcpy(a, c); printf("调用mystrcpy函数的结果："); puts(p); sp = strcpy(a, c); printf("调用strcpy函数的结果："); puts(sp); gets(a); p = mystrcat(c, a); printf("调用mystrcat函数的结果："); puts(p); } return 0;}
2、 输入一行字符串（单词和若干空格）， 输出该行单词个数。
Input ：hello _ world_ how___are___you___\n Output: 5 3. 输入一行字符串（单词和若干空格），输出该行单词（每个单词一行） Input：hello _ world_ how___are___you___\n Output: hello world how are you 4、输入一行字符串，将字符串反转输出//2、输入一行字符串，输出一行单词的个数//3、输入一行字符串，输出一行单词//4、输入一行字符串，将字符串反转#includeint count_number(char* str) { int i = 0; int cnt = 0; int flag = 1; while (str[i]) { if (str[i] != ' ' && flag == 1) { i++; cnt++; flag = 0; } if (str[i] != ' ' && flag == 0) { i++; } if (str[i] == ' ') { i++; flag = 1; } } return cnt;}void print_word(char* str) { int i = 0; int j = 0; char word[50] = { 0}; while (str[i]) { if (str[i] == ' ') { puts(word); memset(word, 0, sizeof(word)); j = 0; i++; } else { word[j] = str[i]; i++; j++; } } puts(word);}char* reserve(char* str1, char *str2) { int len = strlen(str1); int i = 0; len--; for (len; len >= 0; len--) { str2[i] = str1[len]; i++; } str2[i] = 0; //puts(a); return str2;}void reserve_character(char* str1, char* str2) { char* p,* q; p = reserve(str1, str2); int i = 0; int j = 0; char word[50] = { 0 }; char r_word[50] = { 0 }; while (p[i]) { if (p[i] == ' ') { q = reserve(word, r_word); printf("%s ", q); memset(word, 0, sizeof(word)); j = 0; i++; } else { word[j] = p[i]; i++; j++; } } printf("%s ", reserve(word, r_word));}int main() { char c[50]; char a[50] = { 0}; int number; while (gets(c) != NULL) { /*number = count_number(c); printf("该字符串中含有的单词数量为：%d\n", number); print_word(c);*/ printf("反转后的字符串为：\n"); reserve_character(c, a); printf("\n"); } return 0;}
输入一行字符串，将字符串反转的另一种代码格式
转载过来的代码，但一直放在笔记中已经不知道原作者哪位了，仅供参考#include#include void strReverse(char str[]) { //将数组中的内容反转并输出 int slen = strlen(str); for (int i = slen - 1; i >= 0; i--) { putchar(str[i]); } putchar(' ');}int main() { int i = 0, flag = 0, count = 0, word_len = 0; //flag为标志位，用来通过单词间的空格区分单词数量count char str[50]; //原字符串 char word[50]; //现字符串 int slen = 0; printf("请输入长度不超过50的字符串 !!\n"); while (gets(str) != NULL) { slen = strlen(str); //逆序拣选单词，然后再将单词逆序输出。 for (i = slen - 1, count = 0, flag = 0; i >= 0; i--) { if (flag == 0 && str[i] != ' ') { //当前遇到新单词首部，flag标志为0 count++; //单词数量++ flag = 1; //标志位至1 word_len = 0; word[word_len++] = str[i]; } else if (flag == 1 && str[i] != ' ') { //把单词字符逆序加入到数组中 word[word_len++] = str[i]; word[word_len] = '\0'; //末尾加上空字符 flag = 1; } else if (flag == 1 && str[i] == ' ') { //当flag为1，并遇到第一个空格 strReverse(word); //将word数组中的单词反转并输出 word_len = 0; flag = 0; } } strReverse(word); printf("\ncount is %d \n", count); }