i need your help with this. my function is: (the way it works is true)
#include <iostream>
using namespace std;
#define V 4
#define INF 999
int floydWarshall(int graph[][V]){
int dist[V][V], i, j, k;
for (i = 0; i < V; i++)
for (j = 0; j < V; j++)
dist[i][j] = graph[i][j];
for (k = 0; k < V; k++)
{
for (i = 0; i < V; i++)
{
for (j = 0; j < V; j++)
{
if (dist[i][k] + dist[k][j] < dist[i][j])
dist[i][j] = dist[i][k] + dist[k][j];
}
}
}
return dist[V][V];
}
and this line has the error array must be initialized with a brace-enclosed initializer:
int dist[V][V] = floydWarshall(graph[][V]);
You can't use C arrays like other variables or objects in many cases. You can't pass a C array by value to a function or return a C array from a function. It will decay to a pointer to the first element. Therefore std::array was introduced in C++. It does exactly what you expected from C arrays in your code:
#include <array>
constexpr int V = 4;
auto floydWarshall(std::array<std::array<int, V>, V> graph){
for (int k = 0; k < V; k++) {
for (int i = 0; i < V; i++) {
for (int j = 0; j < V; j++) {
if (graph[i][k] + graph[k][j] < graph[i][j])
graph[i][j] = graph[i][k] + graph[k][j];
}
}
}
return graph;
}
With std::array you can pass a copy of the array to the function and don't need to copy it manually. You can return a copy of the array instead of using dynamic memory allocation and pointers.
You use the function with
auto dist = floydWarshall(graph);
where graph has type std::array<std::array<int, V>, V>.
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