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1、.#include #include typedef struct char name100; char pw100;uifo;#define USER_FILE data.bin#define DEFAULT_NAME guest#define DEFAULT_PW 123void write_data(uifo *info) unsigned char len; FILE *fp; fp = fopen(USER_FILE, wb); if(fp = NULL) printf(can not open file n); return; len = strlen(info-name); fw
2、rite(&len, 1, 1, fp); fwrite(info-name, 1, len, fp); len = strlen(info-pw); fwrite(&len, 1, 1, fp); fwrite(info-pw, 1, len, fp); fclose(fp);void read_data(uifo *info) FILE *fp; unsigned char len; fp = fopen(USER_FILE, rb); if(fp = NULL) strcpy(info-name, DEFAULT_NAME); strcpy(info-pw, DEFAULT_PW); w
3、rite_data(info); else memset(info, 0, sizeof *info); fread(&len, 1, 1, fp); fread(info-name, 1, len, fp);精品. fread(&len, 1, 1, fp); fread(info-pw, 1, len, fp); fclose(fp); int main() uifo info; char pw100=0, pw_confirm100=0; int wt = 0; memset(&info, 0, sizeof info); read_data(&info); printf(welcome
4、! please loginn); while(1) printf(please input your user namen); scanf(%s, pw); if(strcmp(pw, info.name) != 0) printf(no such user namen); continue; printf(please input your passwordn); scanf(%s, pw); if(strcmp(pw, info.pw) != 0) printf(password errorn); else break; wt +; if(wt = 3) printf(3 times p
5、assword error, exit!n); return -1; while(1) int i; printf(input 1 to change your passwordninput 0 to exitn); scanf(%d, &i); if(i = 0) break; if(i = 1) 精品. while(1) printf(please input your original passwordn); scanf(%s, pw); if(strcmp(pw, info.pw) != 0) printf(original password is not correctn); con
6、tinue; printf(please input your new passwordn); scanf(%s, pw); printf(please confirm your new passwordn); scanf(%s, pw_confirm); if(strcmp(pw, pw_confirm) != 0) int j; printf(the new passwords are not same in two times input!n); while(1) printf(input 1 to change password againninput 2 to back to last stepninput 0 to exitn); scanf(%d, &j); if(j = 0) return -2; if(j = 1 | j = 2) break; printf(unknown inputn); if(j = 2) break; continue; strcpy(info.pw, pw); write_data(&info); break; else printf(unknown input, should be 0/1n); printf(Bye!n); return 0;如有侵权请联系告知删除，感谢你们的配合！精品