小明有5本书，要借给A、B、C这3位小朋友，若每人每次只能借1本，则可以有多少种不同的借法？
1.定义整形A、B、C；
2.写3重循环；
3.打印结果；
#include<iostream>
using namespace std;
int main()
{
int A, B, C,i = 0;
for (A = 1; A <= 5; A++) {
for (B = 1; B <= 5; B++) {
for (C = 1; C <= 5 && A != B; C++) {
if (A != C && B != C) {
cout <<"A:" << A << " " <<"B:" << B << " " <<"C:" << C << " ";
i++;
if (i % 4 == 0)cout << endl;
}
}
}
}
return 0;
}