[Lydsy2017省队十连测]公路建设

#include<bits/stdc++.h>
#define Mid (l+r>>1)
#define ls no<<1,l,Mid
#define rs no<<1|1,Mid+1,r
#define N 110009
using namespace std;
struct Edge{
    int l,r,co;
}e[N];
int f[107];
struct Node{
    int sum,a[107],to;
    void clear() {
        memset(a,0,sizeof a); sum=0; to=0;
    }
    int fa(int x){
        return f[x]==x?x:f[x]=fa(f[x]);
    }
    inline void join(int xx){
        static int u,v;
        u=fa(e[xx].l); v=fa(e[xx].r);
        if (u==v) return; 
        a[++to]=xx;
        f[u]=v;  sum+=e[xx].co;
    }
    void merge(Node X,Node& Y){
        static int ti,tj,op;
        clear();
        for (int i=1;i<107;i++) f[i]=i;
        ti=1; tj=1;
        while (X.a[ti]&&Y.a[tj]) 
            if (e[X.a[ti]].co<e[Y.a[tj]].co) join(X.a[ti++]);
            else join(Y.a[tj++]);
        while (X.a[ti]) join(X.a[ti++]);
        while (Y.a[tj]) join(Y.a[tj++]);
    }
}t[N<<2],Ans;
void build(int no,int l,int r){
    if (l==r) {
        t[no].sum=e[l].co;
        t[no].a[1]=l;   
        return;
    }
    build(no<<1,l,Mid); build(no<<1|1,Mid+1,r);
    t[no].merge(t[no<<1],t[no<<1|1]);
}
#define sight(x) (‘0‘<=x&&x<=‘9‘)
inline void read(int &x){
    static char c;
    for (c=getchar();!sight(c);c=getchar());
    for (x=0;sight(c);c=getchar())x=x*10+c-48;
}
void write(int x){if (x<10) {putchar(‘0‘+x); return;} write(x/10); putchar(‘0‘+x%10);}
inline void writeln(int x){ if (x<0) putchar(‘-‘),x*=-1; write(x); putchar(‘\n‘); }
inline void writel(int x){ if (x<0) putchar(‘-‘),x*=-1; write(x); putchar(‘ ‘); }
void que(int no,int l,int r,int L,int R){
    if (L<=l&&r<=R) {
        Ans.merge(Ans,t[no]); return;
    }
    if (L<=Mid) que(no<<1,l,Mid,L,R);
    if (R> Mid) que(no<<1|1,Mid+1,r,L,R);
}
int n,m,q,l,r;
signed main () {
   read(n); read(m); read(q);
   for (int i=1;i<=m;i++) 
    read(e[i].l),read(e[i].r),read(e[i].co);
   build(1,1,m);
   while (q--) {
     read(l); read(r);
     Ans.clear();
     que(1,1,m,l,r);
     writeln(Ans.sum);
   }
   return 0;
}