#include<iostream>

#include<cstdio>

#include<cstring>

#include<algorithm>

using namespace std;

#define ll long long

#define ls l,m,rt<<1

#define rs m+1,r,rt<<1|1

const int maxn=;

ll value[maxn<<],add[maxn<<];

void pushup(int rt)//向上更新

{

    value[rt]=value[rt<<]+value[rt<<|];

}

void pushdown(int rt,int m)//向下更新

{

    if(add[rt])

    {

        add[rt<<]=add[rt];//延迟标记向下更新

        add[rt<<|]=add[rt];

        value[rt<<]=(m-(m>>))*add[rt];//价值向下更新

        value[rt<<|]=(m>>)*add[rt];

        add[rt]=;//延迟标记清0

    }

}

void btree(int l,int r,int rt)

{

    add[rt]=;

    if(l==r)

    {

        value[rt]=;

        return ;

    }

    int m=(l+r)>>;

    btree(ls);

    btree(rs);

    pushup(rt);

}

void update(int L,int R,int c,int l,int r,int rt)

{

    if(L<=l&&r<=R)

    {

        add[rt]=c;

        value[rt]=(ll)c*(r-l+);

        return ;

    }

    pushdown(rt,r-l+);

    int m=(l+r)>>;

    if(L<=m)update(L,R,c,ls);

    if(R>m)update(L,R,c,rs);

    pushup(rt);

}

/*ll query(int L,int R,int l,int r,int rt)

{

    if(L<=l&&r<=R)return value[rt];

    pushdown(rt,r-l+1);

    int m=(l+r)>>1;

    ll ans=0;

    if(L<=m)ans+=query(L,R,ls);

    if(R>m)ans+=query(L,R,rs);

    return ans;

}*/

int main()

{

    int t,n,m;

    scanf("%d",&t);

    for(int i=;i<=t;i++)

    {

        scanf("%d%d",&n,&m);

        btree(,n,);

        while(m--){

            int a,b,c;

            scanf("%d%d%d",&a,&b,&c);

            update(a,b,c,,n,);

        }

        printf("Case %d: The total value of the hook is %d.\n",i,value[]);

    }

    return ;

}