Skip to content
Snippets Groups Projects
Commit 97ad24cb authored by Edward Alexander Jaya's avatar Edward Alexander Jaya
Browse files

Not tested parallel program, but at least compileable

parent 2f3770d0
No related merge requests found
Hide whitespace changes
Inline Side-by-side
dijkstra.c
+ 129
− 91
View file @ 97ad24cb
......@@ -4,113 +4,151 @@
#include <stdlib.h>
#include <limits.h>
int NUMBER_OF_VERTICES = 0;
int N = 0;
long getVertexWithMinDistance(long dist[], bool pickedVertices[]) {
long minDistance = LONG_MAX;
int vertexWithMinDistance = -1;
for (int vertex = 0; vertex < NUMBER_OF_VERTICES; vertex++) {
if (!pickedVertices[vertex] && dist[vertex] <= minDistance) {
minDistance = dist[vertex];
vertexWithMinDistance = vertex;
long minDistance = LONG_MAX;
int vertexWithMinDistance = -1;
for (int vertex = 0; vertex < N; vertex++) {
if (!pickedVertices[vertex] && dist[vertex] <= minDistance) {
minDistance = dist[vertex];
vertexWithMinDistance = vertex;
}
}
}
return vertexWithMinDistance;
return vertexWithMinDistance;
}
void dijkstra(int graph[NUMBER_OF_VERTICES][NUMBER_OF_VERTICES], int sourceVertex) {
long* dijkstra(int graph[N][N], int sourceVertex) {
// Distance from single source to all of the nodes
long dist[NUMBER_OF_VERTICES];
bool pickedVertices[NUMBER_OF_VERTICES];
// Distance from single source to all of the nodes
long *dist = (long*) malloc(sizeof(long) * N);
bool pickedVertices[N];
for (int vertex = 0; vertex < NUMBER_OF_VERTICES; vertex++) {
if (vertex == sourceVertex) {
dist[vertex] = 0;
} else {
// Initialize all distance to be infinity.
dist[vertex] = LONG_MAX;
for (int vertex = 0; vertex < N; vertex++) {
if (vertex == sourceVertex) {
dist[vertex] = 0;
} else {
// Initialize all distance to be infinity.
dist[vertex] = LONG_MAX;
}
pickedVertices[vertex] = false;
}
pickedVertices[vertex] = false;
}
for (int iteration = 0; iteration < NUMBER_OF_VERTICES - 1; iteration++) {
// Get minimum distance
int vertexWithMinDistance = getVertexWithMinDistance(dist, pickedVertices);
for (int iteration = 0; iteration < N - 1; iteration++) {
// Get minimum distance
int vertexWithMinDistance = getVertexWithMinDistance(dist, pickedVertices);
// Mark the vertice as picked
pickedVertices[vertexWithMinDistance] = true;
// Update distance value
for (int vertex = 0; vertex < N; vertex++) {
if ((!pickedVertices[vertex]) &&
(graph[vertexWithMinDistance][vertex]) &&
(dist[vertexWithMinDistance] != LONG_MAX) &&
(dist[vertexWithMinDistance] + graph[vertexWithMinDistance][vertex] < dist[vertex])) {
// Change dist[]
dist[vertex] = dist[vertexWithMinDistance] + graph[vertexWithMinDistance][vertex];
}
}
}
// Mark the vertice as picked
pickedVertices[vertexWithMinDistance] = true;
return dist;
// Update distance value
for (int vertex = 0; vertex < NUMBER_OF_VERTICES; vertex++) {
if (!pickedVertices[vertex] && graph[vertexWithMinDistance][vertex] && dist[vertexWithMinDistance] != LONG_MAX && dist[vertexWithMinDistance] + graph[vertexWithMinDistance][vertex] < dist[vertex]) {
dist[vertex] = dist[vertexWithMinDistance] + graph[vertexWithMinDistance][vertex];
}
}
}
// Edit the real graph
for (int vertex = 0; vertex < NUMBER_OF_VERTICES; vertex++) {
graph[sourceVertex][vertex] = dist[vertex];
}
// Print solution
for (int vertex = 0; vertex < NUMBER_OF_VERTICES; vertex++) {
// printf("%d to %ld\n", vertex, dist[vertex]);
printf("%d to %d\n", vertex, graph[sourceVertex][vertex]);
}
// // Print solution
// for (int vertex = 0; vertex < N; vertex++) {
// // printf("%d to %ld\n", vertex, dist[vertex]);
// printf("%d to %d\n", vertex, graph[sourceVertex][vertex]);
// }
}
int main(int argc, char *argv[]) {
// Get matrix size from argument vector in , convert to int
NUMBER_OF_VERTICES = strtol(argv[1], NULL, 10);
// Initialize matrix
int graph[NUMBER_OF_VERTICES][NUMBER_OF_VERTICES];
// Seed with NIM: Edward Alexander Jaya
srand(13517115);
// Fill the matrix with rand() function
for (int i = 0; i < NUMBER_OF_VERTICES; i++) {
for (int j = 0; j < NUMBER_OF_VERTICES; j++) {
// Mod by 100 so the result won't be too big.
graph[i][j] = rand() % 100;
// Test function
// for (int i = 0; i < N; i++) {
// for (int j = 0; j < N; j++) {
// scanf("%d", &graph[i][j]);
// }
// }
// graph = { 0, 4, 0, 0, 0, 0, 0, 8, 0,
// 4, 0, 8, 0, 0, 0, 0, 11, 0,
// 0, 8, 0, 7, 0, 4, 0, 0, 2,
// 0, 0, 7, 0, 9, 14, 0, 0, 0,
// 0, 0, 0, 9, 0, 10, 0, 0, 0,
// 0, 0, 4, 14, 10, 0, 2, 0, 0,
// 0, 0, 0, 0, 0, 2, 0, 1, 6,
// 8, 11, 0, 0, 0, 0, 1, 0, 7,
// 0, 0, 2, 0, 0, 0, 6, 7, 0 };
// dijkstra(graph, 1);
// // Print function
// printf("Matrix: \n");
// for (int i = 0; i < N; i++) {
// for (int j = 0; j < N; j++) {
// printf("%d ", graph[i][j]);
// }
// printf("\n");
// }
// Get matrix size from argument vector in , convert to int
N = strtol(argv[1], NULL, 10);
// Initialize matrix
int graph[N][N];
// Seed with NIM: Edward Alexander Jaya
srand(13517115);
// Fill the matrix with rand() function
for (int i = 0; i < N; i++) {
for (int j = 0; j < N; j++) {
// Mod by 100 so the result won't be too big.
graph[i][j] = rand() % 100;
}
}
}
// Test function
// for (int i = 0; i < NUMBER_OF_VERTICES; i++) {
// for (int j = 0; j < NUMBER_OF_VERTICES; j++) {
// scanf("%d", &graph[i][j]);
// }
// }
// graph = { 0, 4, 0, 0, 0, 0, 0, 8, 0,
// 4, 0, 8, 0, 0, 0, 0, 11, 0,
// 0, 8, 0, 7, 0, 4, 0, 0, 2,
// 0, 0, 7, 0, 9, 14, 0, 0, 0,
// 0, 0, 0, 9, 0, 10, 0, 0, 0,
// 0, 0, 4, 14, 10, 0, 2, 0, 0,
// 0, 0, 0, 0, 0, 2, 0, 1, 6,
// 8, 11, 0, 0, 0, 0, 1, 0, 7,
// 0, 0, 2, 0, 0, 0, 6, 7, 0 };
dijkstra(graph, 1);
// Print function
printf("Matrix: \n");
for (int i = 0; i < NUMBER_OF_VERTICES; i++) {
for (int j = 0; j < NUMBER_OF_VERTICES; j++) {
printf("%d ", graph[i][j]);
MPI_Status Stat;
MPI_Init(&argc, &argv);
// rank is the id of processes, numtasks is the number of processes
int rank, numtasks;
MPI_Comm_size(MPI_COMM_WORLD, &numtasks);
MPI_Comm_rank(MPI_COMM_WORLD, &rank);
double start_time, end_time, total_time = 0.0;
int numOfTaskPerProcess = N / (numtasks - 1);
int destinationRank = 0;
int tag = 1;
int vertex = 0;
// for each thread, synchronize before start
MPI_Barrier(MPI_COMM_WORLD);
// Do not count the initial synchronization time
start_time = MPI_Wtime();
if (rank == 0) {
long* dataRecv;
// Receive
MPI_Recv(&dataRecv, N, MPI_LONG, MPI_ANY_SOURCE, tag, MPI_COMM_WORLD, &Stat);
printf("Received from process %d ", MPI_ANY_SOURCE);
// To do: store in the array
free(dataRecv);
} else {
for (int vertex = (rank - 1) * numOfTaskPerProcess; vertex < (rank - 1) * numOfTaskPerProcess + numOfTaskPerProcess; vertex++) {
long* dataSend = dijkstra(graph, vertex);
MPI_Send(dataSend, N, MPI_LONG, destinationRank, tag, MPI_COMM_WORLD);
// Possible bug
free(dataSend);
}
}
printf("\n");
}
// Send argument vector
MPI_Init(&argc, &argv);
// dijkstra(graph, 0);
MPI_Finalize();
// Synchronize again and count the time
MPI_Barrier(MPI_COMM_WORLD);
end_time = MPI_Wtime();
total_time = end_time - start_time;
MPI_Finalize();
}
prog
+ 0
− 0
View file @ 97ad24cb
No preview for this file type
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment