当运行以下从键盘输入字符串 qwerty 和 abcd, 则程序的输出结果是 _____ 。 #include “string.h” #include “stdio.h” strle(char a[], char b[]) { int num = 0, n = 0; while( *(a + num) != ‘\0’) num ++; while(b[n]) { *(a+num) = b[n]; num ++; n++; } return (num); } main() { char str1[81], str2[81], *p1 = str1, *p2 = str2; gets(p1); gets(p2); printf(“%d\n”, strle(p1, p2)); }