1.IP地址判断是否正确 2.一段字符空格和字母,数字个数 3.给整数输出二进制 #include <stdio.h> #include<iostream> using namespace std; int main() { int n, a, b, c, d; scanf("%d", &n); while (n--){ scanf("%d.%d.%d.%d", &a, &b, &c, &d); if (a < 0 || b < 0 || c < 0 || d < 0 || a > 255 || b > 255 || c > 255 || d > 255) printf("No! "); else printf("Yes! "); } system("pause"); return 0; } #include <iostream> using namespace std; int main() { char c; int letters = 0, space = 0, digit = 0, others = 0; while ((c = getchar())!= ' ') { if (c >= 'a'&&c <= 'z' || c >= 'A'&&c <= 'Z') letters++; else if (c == ' ') space++; else if (c >= '0'&&c <= '9') digit++; else others++; printf("char=%d space=%d digit=%d others=%d ", letters, space, digit, others); system("pause"); return 0; } #include <iostream> using namespace std; int main() { int num ; cin >> num; while(num) { cout << (num&1); num = num >> 1;//把num转换成二进制表示后所有位向后移动一位,高位补0 } cout <<endl; system("pause"); return 0; }