求助 网络流有什么好的debug方法

#include<bits/stdc++.h>
using namespace std;
#define s 2*n+1
#define e 2*n+2
#define LL long long
#define MN 100010
#define MM 1550
#define so(i,j,k,l) for(int i=j;i<=k;i+=l)
#define INF 2100000000
//queue<int>q;
int dep[2*MN],n,h[MN*2],tot,aa[MN],b[MN],sum,m,x,y,z; LL ans;
LL dis[233][233];
struct lll{
	int to,ne,w,op;
	lll(){to=ne=w=op=0;}
}a[MN];
void link(int x,int y,int w)
{
	a[++tot].to=y,a[tot].ne=h[x],h[x]=tot,a[tot].w=w;
}
/*bool bfs(int u)
{
	memset(dep,-1,sizeof(dep));
	while(!q.empty()) q.pop();
	dep[s]=1;q.push(s);
	while (!q.empty())
	{
		for(int i=h[q.front()];i;i=a[i].ne)
		{
			if(dep[a[i].to]==-1&&a[i].w)
			{
				dep[a[i].to]=dep[q.front()]+1;
				q.push(a[i].to);
				if(a[i].to==e) return 1;
			}
		}
		q.pop();
	}
	return 0;
}
int dfs(int u,int nfl)
{
	if(u==e) return nfl;
	int rest = nfl;
	for(int i=h[u];i;i=a[i].ne)
	{
		if(a[i].w&&dep[a[i].to]==dep[u]+1&&rest)
		{
			int nwf=dfs(a[i].to,min(rest,a[i].w));
			rest-=nwf;
			a[a[i].op].w+=nwf;
			a[i].w-=nwf;
		}
	}
	return nfl-rest;
}*/
bool bfs(int u)
{
    memset(dep,-1,sizeof(dep));
    int tt=0,hh=0,q[MN];dep[s]=1;q[++tt]=s;
    while(hh<tt)
    {
        int v=q[++hh];
        for(int i=h[v];i;i=a[i].ne)
        {
            if(dep[a[i].to]==-1&& a[i].w)
            {
                
                dep[a[i].to]=dep[v]+1;
                q[++tt]=a[i].to;
                if(a[i].to==e) return 1;
            }
        }
    }
    return 0;
}
int dfs(int u,int nfl)
{
    if(u==e) return nfl;
    int rest = nfl;
    for(int i=h[u];i;i=a[i].ne)
    {
        if(a[i].w&&dep[a[i].to]==dep[u]+1&&rest)
        {
            int nwf=dfs(a[i].to,min(rest,a[i].w));
            a[i].w-=nwf;
            a[a[i].op].w+=nwf;
            rest-=nwf;
        }
    }
    return nfl-rest;
}
LL can(LL mid)
{
	so(i,1,tot,1) a[i].ne=a[i].to=a[i].w=a[i].op=0,h[i]=0;
	tot=0,ans=0;
	so(i,1,n,1) so(j,i+1,n,1) 
	{
		if(dis[i][j]<=mid) 
		link(i,j+n,INF),link(j+n,i,0),a[tot-1].op=tot,
		link(j,i+n,INF),link(i+n,j,0),a[tot-1].op=tot;
	}
	so(i,1,n,1) 
	link(s,i,aa[i]),link(i,s,0),a[tot-1].op=tot,
	link(i+n,e,b[i]),link(e,i+n,0),a[tot-1].op=tot,
	link(i,n+i,INF),link(n+i,i,0),a[tot-1].op=tot;
	//for(int i=h[s];i;i=a[i].ne) printf("%d#%d ",a[i].to,a[i].w);
	while(bfs(s)) 
	ans+=dfs(s,INF);
	return ans;
}
int main()
{
	//memset(dis,,sizeof(dis));cout<<dis[0];
	scanf("%d%d",&n,&m);so(i,1,n,1) so(j,1,n,1) dis[i][j]=1e19;
	so(i,1,n,1) scanf("%d%d",&aa[i],&b[i]),sum+=aa[i];
	so(i,1,m,1) scanf("%d%d%d",&x,&y,&z),dis[x][y]=dis[y][x]=min((LL)z,dis[y][x]);
	so(i,1,n,1) dis[i][i]=0;
	so(k,1,n,1) so(i,1,n,1) so(j,1,n,1) dis[i][j]=min(dis[i][j],dis[i][k]+dis[k][j]);
	LL l=0,r=1e9*m;
	//so(i,1,n,1) {so(j,1,n,1) printf("%d ",dis[i][j]);cout<<endl;}
	while(l<=r)
	{
		LL mid=(l+r)>>1;
		if(can(mid)>=sum) r=mid-1;
		else l=mid+1;
	}
	if(r==1e9*m) printf("-1");
	else printf("%lld",l);
	return 0;
}