(数字删除)下面程序的功能是将字符串中的数字字符删除后输出。请填空。
#include <iostream> using namespace std; int delnum(char *s) { int i, j; j = 0; for (i = 0; s[i] != '\0'; i++) if (s[i] < '0' (1) > '9') { s[j] = s[i]; (2) ; } return (3) ; } const int SIZE = 30; int main() { char s[SIZE]; int len, i; cin.getline(s, sizeof(s)); len = delnum(s); for (i = 0; i < len; i++) cout<< (4) ; cout << endl; return 0; }