c语言计算整数型行列式

 1 #include <stdio.h>
 2
 3 void showDet(int n,int d[n][n]);
 4 int getVal(int n,int d[n][n]);
 5 int getA(int n,int d[n][n],int x,int y);
 6
 7 int main(int argc, char *argv[])
 8 {
 9     do{
10         int n,i,j;
11         printf("请输入行列式的阶数(输入0退出):\n");
12         scanf("%d",&n);
13         if(n==0) break;
14         printf("请输入行列式(空格分隔):\n");
15         int d[n][n];
16         for(i=0;i<n;i++){
17             for(j=0;j<n;j++){
18                 scanf("%d",&d[i][j]);
19             }
20         }
21         printf("\n输入行列式如下:\n");
22         showDet(n,d);
23         printf("\n该行列式的值为:\n%d\n\n\n",getVal(n,d));
24
25     }while(1);
26     return 0;
27 }
28
29 void showDet(int n,int d[n][n]){
30     int i,j;
31     for(i=0;i<n;i++){
32         for(j=0;j<n;j++){
33             printf("%d\t",d[i][j]);
34         }
35         printf("\n");
36     }
37 }
38
39 int getVal(int n,int d[n][n]){
40     if(n == 1) return d[0][0];
41     int i,j,sum=0;
42
43     for(i=0;i<n;i++){
44         sum=sum+d[0][i]*getA(n,d,1,i+1);
45     }
46     return sum;
47 }
48
49 int getA(int n,int d[n][n],int x,int y){
50     int a[n-1][n-1],i,j;
51     for(i=0;i<n;i++){
52         if(i==x-1) continue;
53         for(j=0;j<n;j++){
54             if(j==y-1) continue;
55             else if(i<x-1 && j<y-1){
56                 a[i][j]=d[i][j];
57             } else if(i<x-1 && j>y-1){
58                 a[i][j-1]=d[i][j];
59             }else if(i>x-1 && j<y-1){
60                 a[i-1][j]=d[i][j];
61             }else if(i>x-1 && j>y-1){
62                 a[i-1][j-1]=d[i][j];
63             }
64         }
65     }
66     int t;
67      t = (x+y)%2 == 0 ? 1:-1;
68     return t*getVal(n-1,a);
69 }