1.步骤
（1）.数据的标准化处理；
（2）.选出最优方案和最劣方案；
（3）.计算出各个对象和最优以及最劣之间的距离；
（4）.再使用Dbest/(Dbest+Dwors)计算出各对象的评分，值越小的评价越高，依次排序；
2.源代码
#include <iostream>
#define m 8
#define n 3
void max(float a[][n], float b[], float c[]);
int main()
{
FILE* fpr, * fpw;
fopen_s(&fpr, "1.txt", "r");
fopen_s(&fpw, "2.txt", "w");
float sum = 0.0, aver, c = 0.0, r, minn[n], maxx[n], s1 = 0.0, s2 = 0.0, s[m][2], best[m], z, a[m][n];
int sort[m];
for (int i = 0; i < m; i++)//读取数据
for (int j = 0; j < n; j++)
fscanf_s(fpr, "%f", &a[i][j]);
/* for (int j = 0; j < n; j++)//具体题目具体改编，逆数据取倒
for (int i = 0; i < m; i++)
a[i][j] = 1.0 / a[i][j];*/
max(a, maxx, minn);//求最值
for (int j = 0; j < n; j++)//极差标准化处理
for (int i = 0; i < m; i++)
a[i][j] = (a[i][j] - minn[j]) / (maxx[j] - minn[j]);
/* for (int j = 0; j < n; j++)//求各列之和
for (int i = 0; i < m; i++)
sum += a[i][j];
aver = sum / (n * m);
for (int j = 0; j < n; j++)
for (int i = 0; i < m; i++)
c += abs((a[i][j] - aver) * (a[i][j] - aver) / (n * m));
r = sqrt(c);//标准差求解
for (int j = 0; j < n; j++)//归一化处理(z-score 0均值标准化)
for (int i = 0; i < m; i++)
a[i][j] = (a[i][j]-aver) / r;*/
max(a, maxx, minn);//求最值
fprintf(fpw,"归一化处理后的数据为：\n");
for (int j = 0; j < m; j++)
{
for (int i = 0; i < n; i++)
fprintf(fpw,"%f ", a[j][i]);
fprintf(fpw,"\n");
}
max(a, maxx, minn);//求最值
for (int j = 0; j < m; j++)//求正负距离
{
for (int i = 0; i < n; i++)
{
s1 += (a[j][i] - maxx[i]) * (a[j][i] - maxx[i]);
s2 += (a[j][i] - minn[i]) * (a[j][i] - minn[i]);
}
s[j][0] = sqrt(s1);
s[j][1] = sqrt(s2);
}
for (int j = 0; j < m; j++)//求每组距离的最大值
{
z = s[j][0];
for (int i = 0; i < 2; i++)
if (z < s[j][i])
z = s[j][i];
best[j] = z;
}
for (int i = 0; i < m; i++)
best[i] = best[i] / (s[i][0] + s[i][1]);
fprintf(fpw,"\n最优数据为：\n");
for (int i = 0; i < n; i++)
fprintf(fpw,"%f ", maxx[i]);
fprintf(fpw,"\n");
fprintf(fpw,"\n最差数据为：\n");
for (int i = 0; i < n; i++)
fprintf(fpw,"%f ", minn[i]);
fprintf(fpw,"\n");
fprintf(fpw,"\n每组数据的正负距离为：\n");
for (int j = 0; j < m; j++)
{
for (int i = 0; i < 2; i++)
fprintf(fpw,"%f ", s[j][i]);
fprintf(fpw,"\n");
}
fprintf(fpw,"\n每组数据的权值为：\n");
for (int i = 0; i < m; i++)
fprintf(fpw,"%f\n", best[i]);
for (int i = 0; i < m; i++)
sort[i] = 1;
for (int i = 0; i < m; i++)
for (int j = 0; j < m; j++)
if (best[j] < best[i])
sort[i] += 1;
fprintf(fpw,"\n各数据排名为：\n");
for (int i = 0; i < m; i++)
fprintf(fpw,"%d\n", sort[i]);
return 0;
}
void max(float a[][n], float b[], float c[])//求最大及最小值
{
for (int i = 0; i < n; i++)
b[i] = c[i] = a[0][i];
for (int j = 0; j < n; j++)
for (int i = 0; i < m; i++)
{
if (a[i][j] > b[j])
b[j] = a[i][j];
if (a[i][j] < c[j])
c[j] = a[i][j];
}
}3.I/O（输入和输出放在txt文件内）
输入：
1150.3 3565.71 69
1189.7 3656.705 69
1193.7 3618.585 69
1221.9 3624.21 72
1229.8 3591.705 83
1230.6 3630.495 86
1276.1 3594.075 93
1337.7 3614.955 102
输出：
归一化处理后的数据为：
0.000000 0.000000 0.000000
0.210245 1.000000 0.000000
0.231590 0.581075 0.000000
0.382071 0.642892 0.090909
0.424226 0.285676 0.424242
0.428495 0.711963 0.515152
0.671291 0.311720 0.727273
1.000000 0.541184 1.000000
最优数据为：
1.000000 1.000000 1.000000
最差数据为：
0.000000 0.000000 0.000000
每组数据的正负距离为：
1.732051 0.000000
2.150282 1.021863
2.527779 1.198117
2.779474 1.415287
2.983076 1.563521
3.089240 1.844038
3.193676 2.115941
3.226465 2.601939
每组数据的权值为：
1.000000
0.677864
0.678435
0.662606
0.656112
0.626204
0.601489
0.553576
各数据排名为：
8
6
7
5
4
3
2
1
