Submission #3926327

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Source Code Expand

#include <cstdio>
#include <iostream>
using namespace std;
int N, M, arr[100005], parent[100005], result;

int find(int node)
{
    if(node == parent[node])
    {
        return node;
    }
    return parent[node] = find(parent[node]);
}

void uni(int node1, int node2)
{
    int p1, p2;
    p1 = find(node1);
    p2 = find(node2);
    if(p1 != p2)
    {
        parent[p2] = p1;
    }
}

int main()
{
    scanf("%d %d", &N, &M);
    for(int i = 1; i <= N; i++)
    {
        parent[i] = i;
        scanf("%d", &arr[i]);
    }
    for(int i = 0; i < M; i++)
    {
        int x, y;
        scanf("%d %d", &x, &y);
        uni(x, y);
    }
    for(int i = 1; i <= N; i++)
    {
        if(find(i) == find(arr[i]) || arr[i] == i)
        {
            result++;
        }
    }
    printf("%d", result);
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:28:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d", &N, &M);
                           ^
./Main.cpp:32:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d", &arr[i]);
                             ^
./Main.cpp:37:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d %d", &x, &y);
                               ^

Judge Result