Cod sursa(job #2741752)

Utilizator luca_raduluca 123 luca_radu Data 18 aprilie 2021 17:56:16
Problema Algoritmul lui Dijkstra Scor 40
Compilator c-64 Status done
Runda Arhiva educationala Marime 1.92 kb
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int N, M;

#define inf 1000000001

typedef struct graphMatrix {
	int** costMatrix;
} graphMatrix;

typedef struct nodeNDP {
	int node;
	int d;
	int parent;
} nodeNDP;

graphMatrix readFile(const char* filename)
{
	graphMatrix graph;
	FILE* f = fopen(filename, "r");

	fscanf(f, "%d %d", &N, &M);
	graph.costMatrix = (int**)malloc(sizeof(int*) * N);
	int i, j;
	for (i = 0; i < N; i++) {
		graph.costMatrix[i] = (int*)malloc(sizeof(int) * N);
		for (j = 0; j < N; j++) {
			if (i == j) {
				graph.costMatrix[i][j] = 0;
				continue;
			}
			graph.costMatrix[i][j] = inf;
		}
	}
	short A, B, C;
	for (i = 0; i < M; i++) {
		fscanf(f, "%hd %hd %hd", &A, &B, &C);
		graph.costMatrix[A - 1][B - 1] = C;
	}

	fclose(f);
	return graph;
}

nodeNDP* dijkstra(graphMatrix graph, int source)
{
	nodeNDP* NDP = (nodeNDP*)malloc(sizeof(nodeNDP) * (N + 1));
	int visited[5000] = {0};
	for (int i = 1; i <= N; i++) {
		NDP[i].node = i;
		NDP[i].d = inf;
		NDP[i].parent = -1;
	}
	source--;
	NDP[source].d = 0;
	int count = 1;
	int min;
	int i;
	while (count <= N - 1) {
		for (i = 0; i < N; i++) {
			if (source != i && graph.costMatrix[source][i] != inf && visited[i] == 0) {
				int distance = NDP[source].d + graph.costMatrix[source][i];
				if (distance < NDP[i].d) {
					NDP[i].d = distance;
					NDP[i].parent = source;
				}
			}
		}
		visited[source] = 1;
		count++;
		min = inf;
		for (i = 1; i <= N; i++) {
			if (min > NDP[i].d && visited[i] == 0) {
				min = NDP[i].d;
				source = i;
			}
		}
	}
	return NDP;
}

int main()
{
	graphMatrix graph = readFile("dijkstra.in");
	nodeNDP* NDP = dijkstra(graph, 1);
	FILE* f = fopen("dijkstra.out", "w");
	for (int i = 1; i < N; i++) {
		if (NDP[i].d == inf) {
			fprintf(f, "%d ", 0);
		} else {
			fprintf(f, "%d ", NDP[i].d);
		}
	}

	for (int i = 0; i < N; i++) {
		free(graph.costMatrix[i]);
	}
	free(graph.costMatrix);
	free(NDP);
	fclose(f);

	return 0;
}