buuoj-[WUSTCTF2020]Cr0ssfun

1.64bit nowinexe 直接打开

2.找到main函数

当check（flag）这个函数==1的时候，才正确

3.步入：

耐心一点，一个一个扣出来就行了。。。

a1=[0]*33
a1[10] = 112
a1[13] = 64
a1[3] = 102
a1[26] = 114
a1[20] = 101
a1[7] = 48
a1[16] = 95
a1[11] = 112
a1[23] = 101
a1[30] = 117
a1[0] = 119
a1[6] = 50
a1[22] = 115
a1[31] = 110
a1[12] = 95
a1[15] = 100
a1[8] = 123
a1[18] = 51
a1[28] = 95
a1[21] = 114
a1[2] = 116
a1[9] = 99
a1[32] = 125
a1[19] = 118
a1[5] = 48
a1[14] = 110
a1[4] = 50
a1[17] = 114
a1[29] = 102
a1[17] = 114
a1[24] = 95
a1[1] = 99
a1[25] = 64
a1[27] = 101
for i in range(len(a1)):
    print(chr(a1[i]),end='')

得到

wctf2020{cpp_@nd_r3verse_@re_fun}