GRAPHS---Minimum number of swaps required to sort an array

int minSwaps(int a[], int n){
    int i,j,ans=0,vis[n],c;
    for(i=0;i<n;i++)
    vis[i]=0;
    pair<int,int>p[n];
    for(i=0;i<n;i++)
    {
        p[i].first=a[i];
        p[i].second=i;
    }
    sort(p,p+n);
    for(i=0;i<n;i++)
    {
        if(vis[i]==1||p[i].second==i)
        continue;
        c=0;
        j=i;
        while(vis[j]!=1)
        {
            vis[j]=1;
            j=p[j].second;
            c++;
        }
        ans+=c-1;
    }
    return ans;
}