题解

#include<bits/stdc++.h>
using namespace std;

#define MAXN 200000
#define MAXM 200000
#define INF 0x3f3f3f3f
typedef long long int LL;

struct things
{
    int w,val;
    things(){}
    things(int a,int b):w(a),val(b){}

    bool operator < (const things &a)const
    {
        return w>a.w;
    }
}A[MAXN+10];

int N,M;
LL S;
int L[MAXM+10],R[MAXM+10];
int MinW=INF,MaxW=-INF;
LL sum[MAXN+10];
int num[MAXN+10];

LL Gety(int W)
{
    LL rn=0;

    sum[0]=num[0]=0;
    for(int i=1;i<=N;++i)
    {
        num[i]=num[i-1]+(A[i].w>=W);
        sum[i]=sum[i-1]+(A[i].w>=W?A[i].val:0);
    }

    for(int i=1;i<=M;++i)
        rn+=(num[R[i]]-num[L[i]-1])*(sum[R[i]]-sum[L[i]-1]);

    return rn;
}

int main()
{
    cin>>N>>M>>S;
    int i,j;

    for(i=1;i<=N;++i)
    {
        cin>>A[i].w>>A[i].val;

        MinW=min(MinW,A[i].w);
        MaxW=max(MaxW,A[i].w);
    }

    for(i=1;i<=M;++i)
        cin>>L[i]>>R[i];

    LL maxval=Gety(MinW),minval=Gety(MaxW);
    if(maxval<=S)
    {
        cout<<S-maxval<<'\n';
        return 0;
    }
    if(minval>=S)
    {
        cout<<minval-S<<'\n';
        return 0;
    }

    int l=MinW,r=MaxW;
    LL ans=0x3f3f3f3f3f3f3f3fll;
    while(l<r)
    {
        int mid=(l+r)>>1;
        LL val=Gety(mid);
        ans=min(ans,abs(S-val));

        if(val<S)r=mid-1;
        else l=mid+1;
    }

    ans=min(ans,min(abs(Gety(l)-S),abs(Gety(r)-S)));
    cout<<ans<<'\n';
}

内存时间都是最优