#include <stdio.h>
#include <stdlib.h>
#include <time.h>
int main(void)
{
char gesture[3][10] = { "scissor", "stone", "cloth" };
int man, computer, result, ret;
srand(time(NULL));
while (1)
{
computer = rand() % 3;
printf("\nInput your gesture (0-scissor 1-stone 2-cloth):\n");
ret = scanf("%d", &man);
if (ret != 1 || man < 0 || man > 2)
{ printf("Invalid input! Please input 0, 1 or 2.\n");
continue; }
printf("Your gesture: %s\tComputer's gesture: %s\n", gesture[man], gesture[computer]);
result = (man - computer + 4) % 3 - 1;
if (result > 0) printf("You win!\n");
else if (result == 0) printf("Draw!\n");
else printf("You lose!\n"); } return 0;}
这是c语言石头剪子布游戏的code,请问“(man - computer + 4) % 3 - 1”这个表达式的思路是什么呢?谢谢!