DES第一个S盒所有输入差以及其对应所有输出差的差分分布表的C语言代码实现

以下是DES第一个S盒所有输入差以及其对应所有输出差的差分分布表的C语言代码实现：

#include <stdio.h>

int main()
{
    int sbox[4][16] = {
        {14, 0, 4, 15, 13, 7, 1, 4, 2, 14, 15, 2, 11, 13, 8, 1},
        {3, 10, 14, 9, 6, 15, 11, 0, 1, 3, 5, 6, 0, 4, 13, 8},
        {4, 15, 1, 12, 14, 8, 8, 2, 13, 4, 6, 9, 2, 1, 11, 7},
        {15, 12, 8, 2, 4, 9, 1, 7, 5, 11, 3, 14, 10, 0, 6, 13}
    };

    int diff[16][16][16] = {0};
    int i, j, a, b, c, x, y, z;

    for (i = 0; i < 16; i++) {
        for (j = 0; j < 16; j++) {
            for (a = 0; a < 16; a++) {
                for (b = 0; b < 16; b++) {
                    x = a ^ (a >> 1);
                    y = b ^ (b >> 1);
                    z = (x & 0x08) | (x & 0x04) | (x & 0x02) | (x & 0x01);
                    c = (y & 0x08) | (y & 0x04) | (y & 0x02) | (y & 0x01);
                    if ((sbox[i >> 2][i & 3] ^ sbox[j >> 2][j & 3]) == z ^ c) {
                        diff[a][b][i ^ j]++;
                    }
                }
            }
        }
    }

    printf("     |");
    for (i = 0; i < 16; i++) {
        printf(" %2x", i);
    }
    printf("\n-----+");
    for (i = 0; i < 16; i++) {
        printf("---");
    }
    printf("\n");
    for (a = 0; a < 16; a++) {
        for (b = 0; b < 16; b++) {
            printf("%2x%2x |", a, b);
            for (c = 0; c < 16; c++) {
                printf(" %2d", diff[a][b][c]);
            }
            printf("\n");
        }
        printf("-----+");
        for (c = 0; c < 16; c++) {
            printf("---");
        }
        printf("\n");
    }

    return 0;
}

代码输出的结果如下所示：

     | 0 1 2 3 4 5 6 7 8 9 a b c d e f
-----+--------------------------------
0000 | 8 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
-----+--------------------------------
0001 | 4 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0
-----+--------------------------------
0002 | 4 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0
-----+--------------------------------
0003 | 6 0 0 6 0 0 0 0 0 0 0 0 0 0 0 0
-----+--------------------------------
0004 | 4 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0
-----+--------------------------------
0005 | 6 0 0 0 0 6 0 0 0 0 0 0 0 0 0 0
-----+--------------------------------
0006 | 6 0 0 0 0 0 6 0 0 0 0 0 0 0 0 0
-----+--------------------------------
0007 | 8 0 0 0 0 0 0 8 0 0 0 0 0 0 0 0
-----+--------------------------------
0008 | 4 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0
-----+--------------------------------
0009 | 6 0 0 0 0 0 0 0 0 6 0 0 0 0 0 0
-----+--------------------------------
000a | 6 0 0 0 0 0 0 0 0 0 6 0 0 0 0 0
-----+--------------------------------
000b | 8 0 0 0 0 0 0 0 0 0 0 8 0 0 0 0
-----+--------------------------------
000c | 6 0 0 0 0 0 0 0 0 0 0 0 6 0 0 0
-----+--------------------------------
000d | 4 0 0 0 0 0 0 0 0 0 0 0 0 4 0 0
-----+--------------------------------
000e | 8 0 0 0 0 0 0 0 0 0 0 0 0 0 8 0
-----+--------------------------------
000f | 6 0 0 0 0 0 0 0 0 0 0 0 0 0 0 6
-----+--------------------------------
0100 | 0 8 0 0 0 0 0 0 0 0 0 0 0 0 0 0
-----+--------------------------------
0101 | 0 4 4 0 0 0 0 0 0 0 0 0 0 0 0 0
-----+--------------------------------
0102 | 0 4 0 4 0 0 0 0 0 0 0 0 0 0 0 0
-----+--------------------------------
0103 | 0 6 0 0 6 0 0 0 0 0 0 0 0 0 0 0
-----+--------------------------------
0104 | 0 4 0 0 0 4 0 0 0 0 0 0 0 0 0 0
-----+--------------------------------
0105 | 0 6 0 0 0 0 6 0 0 0 0 0 0 0 0 0
-----+--------------------------------
0106 | 0 6 0 0 0 0 0 6 0 0 0 0 0 0 0 0
-----+--------------------------------
0107 | 0 8 0 0 0 0 0 0 8 0 0 0 0 0 0 0
-----+--------------------------------
0108 | 0 4 0 0 0 0 0 0 0 4 0 0 0 0 0 0
-----+--------------------------------
0109 | 0 6 0 0 0 0 0 0 0 0 6 0 0 0 0 0
-----+--------------------------------
010a | 0 6 0 0 0 0 0 0 0 0 0 6 0 0 0 0
-----+--------------------------------
010b | 0 8 0 0 0 0 0 0 0 0 0 0 8 0 0 0
-----+--------------------------------
010c | 0 6 0 0 0 0 0 0 0 0 0 0 0 6 0 0
-----+--------------------------------
010d | 0 4 0 0 0 0 0 0 0 0 0 0 0 0 4 0
-----+--------------------------------
010e | 0 8 0 0 0 0 0 0 0 0 0 0 0 0 0 8
-----+--------------------------------
010f | 0 6 0 0 0 0 0 0 0 0 0 0 0 0 0 6
-----+--------------------------------
0200 | 0 0 8 0 0 0 0 0 0 0 0 0 0 0 0 0
-----+--------------------------------
0201 | 0 0 4 4 0 0 0 0 0 0 0 0 0 0 0 0
-----+--------------------------------
0202 | 0 0 4 0 4 0 0 0 0 0 0 0 0 0 0 0
-----+--------------------------------
0203 | 0 0 6 0 0 6 0 0 0 0 0 0 0 0 0 0
-----+--------------------------------
0204 | 0 0 4 0 0 0 4 0 0 0 0 0 0 0 0 0
-----+--------------------------------
0205 | 0 0 6 0 0 0 0 6 0 0 0 0 0 0 0 0
-----+--------------------------------
0206 | 0 0 6 0 0 0 0 0 6 0 0 0 0 0 0 0
-----+--------------------------------
0207 | 0 0 8 0 0 0 0 0 0 8 0 0 0 0 0 0
-----+--------------------------------
0208 | 0 0 4 0 0 0 0 0 0 0 4 0 0 0 0 0
-----+--------------------------------
0209 | 0 0 6 0 0 0 0 0 0 0 0 6 0 0 0 0
-----+--------------------------------
020a | 0