無聊曬一下短路用法
https://ideone.com/vYvznk
#include <cstdio>
int f(int i, int j, int k) {
return (i > 8) ||
printf("%d x%2d =%2d%c", i + 1, j + 1, k + i + 1, "\n|"[!(j & 8)]) &&
f(i + !!(j & 8), "123456780"[j] - '0', -!(j & 8) & (k + i + 1));
}
int main() {
f(0, 0, 0);
return 0;
}