mirror of https://github.com/TheAlgorithms/C
83 lines
2.8 KiB
C
83 lines
2.8 KiB
C
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#include <stdio.h>
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#include <stdbool.h>
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#include "Graph.h"
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// Return the number of vertices that v is
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// connected to
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int degree(Graph g, int nV, Vertex v) {
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int deg = 0;
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Vertex w;
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for (w = 0; w < nV; w++)
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if (adjacent(g, v, w))
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deg++;
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return deg;
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}
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// If start from vertex v, decide if the
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// graph has euler path
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bool hasEulerPath(Graph g, int nV, Vertex v, Vertex w) {
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if (v != w) {
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if (degree(g, nV, v) % 2 == 0 || degree(g, nV, w) % 2 == 0)
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return false;
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} else if (degree(g, nV, v) % 2 != 0) {
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return false;
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}
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Vertex x;
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for (x = 0; x < nV; x++)
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if (x != v && x != w && degree(g, nV, x) % 2 != 0)
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return false;
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return true;
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}
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int main(void) {
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Edge e;
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int n;
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printf("Enter the number of vertices: ");
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scanf("%d", &n);
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Graph g = newGraph(n);
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Vertex src, dest;
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printf("Enter source node: ");
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scanf("%d", &src);
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printf("Enter destination node: ");
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scanf("%d", &dest);
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printf("Enter an edge (from): ");
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while (scanf("%d", &e.v) == 1) {
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printf("Enter an edge (to): ");
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scanf("%d", &e.w);
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insertEdge(g, e);
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printf("Enter an edge (from): ");
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}
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printf("Finished.\n");
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printf("The graph has ");
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if (hasEulerPath(g, n, src, dest))
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printf("an");
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else
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printf("no");
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printf(" Euler path from %d to %d.\n", src, dest);
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freeGraph(g);
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return 0;
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}
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// By
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// .----------------. .----------------. .----------------. .-----------------. .----------------. .----------------.
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// | .--------------. || .--------------. || .--------------. || .--------------. | | .--------------. || .--------------. |
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// | | _________ | || | _____ _____ | || | __ | || | ____ _____ | | | | ____ ____ | || | ____ | |
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// | | | _ _ | | || ||_ _||_ _|| || | / \ | || ||_ \|_ _| | | | | |_ || _| | || | .' `. | |
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// | | |_/ | | \_| | || | | | | | | || | / /\ \ | || | | \ | | | | | | | |__| | | || | / .--. \ | |
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// | | | | | || | | ' ' | | || | / ____ \ | || | | |\ \| | | | | | | __ | | || | | | | | | |
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// | | _| |_ | || | \ `--' / | || | _/ / \ \_ | || | _| |_\ |_ | | | | _| | | |_ | || | \ `--' / | |
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// | | |_____| | || | `.__.' | || ||____| |____|| || ||_____|\____| | | | | |____||____| | || | `.____.' | |
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// | | | || | | || | | || | | | | | | || | | |
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// | '--------------' || '--------------' || '--------------' || '--------------' | | '--------------' || '--------------' |
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// '----------------' '----------------' '----------------' '----------------' '----------------' '----------------'
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// Email : z5261243@unsw.edu.au
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// hhoanhtuann@gmail.com
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