1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
|
#include <stdio.h>
int A[10][10], n, d[10], p[10];
int bellman_ford() {
int i, u, v;
for (int i = 0; i < n; i++) {
for (u = 0; u < n; u++) {
for (v = 0; v < n; v++) {
if (d[v] > d[u] + A[u][v]) {
d[v] = d[u] + A[u][v];
p[v] = u;
}
}
}
}
for (u = 0; u < n; u++) {
for (v = 0; v < n; v++) {
if (d[v] > d[u] + A[u][v]) {
printf("Detected negative edge\n");
return -1;
}
}
}
return 0;
}
int main() {
scanf("%d", &n);
int source = 0, destination = 0;
for (int i = 0; i < n; i++) {
for (int j = 0; j < n; j++) {
scanf("%d", &A[i][j]);
}
}
scanf("%d", &source);
scanf("%d", &destination);
printf("Input graph:\n");
for (int i = 0; i < n; i++) {
for (int j = 0; j < n; j++) {
printf("%3d ", A[i][j]);
}
printf("\n");
}
for (int i = 0; i < n; i++) {
d[i] = 999;
p[i] = -1;
}
d[source] = 0;
int valid = bellman_ford();
if (valid == -1) {
printf("Graph contains negative edge\n");
return 0;
}
printf("\nFrom Router %d to Router %d\n", source, destination);
// for(int i=0; i<n; i++){
// printf("Cost: %2d | Path: ", d[i]);
// if(i != source){
// int j = i;
// while(p[j] != -1){
// printf("%d <- ",j);
// j = p[j];
// }
// }
// printf("%d\n",source);
// }
printf("Cost: %2d | Path: ", d[destination]);
if(destination != source){
int j = destination;
while(p[j] != -1){
printf("%d <- ",j);
j = p[j];
}
}
printf("%d\n",source);
}
|
