C语言将字符串转换成对应的数目字(十进制、十六进制)

C语言将字符串转换成对应的数字(十进制、十六进制)

??????? 问题1：讲一个十进制数字的字符串表示转换成对应的整数。举例：将“1234”转换成整数1234.

//将十六进制的字符串转换成整数int htoi(char s[]){int i;int n = 0;if (s[0] == '0' && (s[1]=='x' || s[1]=='X')){i = 2;}else{i = 0;}for (; (s[i] >= '0' && s[i] <= '9') || (s[i] >= 'a' && s[i] <= 'z') || (s[i] >='A' && s[i] <= 'Z');++i){if (tolower(s[i]) > '9'){n = 16 * n + (10 + tolower(s[i]) - 'a');}else{n = 16 * n + (tolower(s[i]) - '0');}}return n;}