1.String reverse order all string.
#include <stdio.h> #include <string.h> /* *"abcdefg"->"gfedcba" */ void reverse(char *p, char *q) { char tmp = 0; while(p<q){ /*exchange*/ tmp = *q; *q = *p; *p = tmp; p++; q--; } return; } int main() { char str[100] = {0}; char *p = str;/*head*/ char *q = NULL; scanf("%s", str); q = &str[strlen(str)-1];/*tail*/ reverse(p, q);/*head and tail exchange*/ printf("%s\n", str); return 0; }2.String reverse order as word.
#include <stdio.h> #include <string.h> /* *"hua wei niu bi"->"auh iew uin ib"->"bi niu wei hua" */ void reverse(char *p, char *q) { char tmp = 0; while(p<q){ tmp = *q; *q = *p; *p = tmp; p++; q--; } return; } int main() { char str[100] = {0}; char *p = str;/*word head*/ char *q = str;/*space*/ fgets(str, 100, stdin); str[strlen(str)-1] = 0;/*lastest is '\n'*/ while(*q != '\0'){ if (*q == ' '){ reverse(p, q-1); q++; p = q; }else{ q++; } } reverse(p, q-1);/*lastest word*/ reverse(str, q-1);/*all string*/ printf("%s\n", str); return 0; }
