P1314 聪明的质监员

#include<bits/stdc++.h>
using namespace std;
int n,m,l=-1,r=0x3f3f3f3f;
long long s,sum,cn[2000000],su[2000000],ans=0x3f3f3f3f3f3f3f3f;
struct node{int w,v;}num[2000000];
struct md{int l,r;}tq[2000000];
int read()
{int fg=1,cn=0;char ch=getchar();
while(ch<‘0‘||ch>‘9‘){if(ch==‘-‘)fg=-1;ch=getchar();}
while(ch>=‘0‘&&ch<=‘9‘){cn=(cn<<1)+(cn<<3)+(ch^48);ch=getchar();}
return fg*cn;}
int bl(int w)
{
    sum=0;
    memset(cn,0,sizeof(cn));memset(su,0,sizeof(su));
    for(int i=1;i<=n;i++)
    {
        if(num[i].w>=w)cn[i]=cn[i-1]+1,su[i]=su[i-1]+num[i].v;
        else cn[i]=cn[i-1],su[i]=su[i-1];
    }
    for(int i=1;i<=m;i++)
    sum+=((cn[tq[i].r]-cn[tq[i].l-1])*(su[tq[i].r]-su[tq[i].l-1]));
    if(sum>s)return 1;
    else return 0;
}
int main()
{
    cin>>n>>m>>s;
    for(int i=1;i<=n;i++){num[i].w=read();num[i].v=read();
    r=max(r,num[i].w);l=min(l,num[i].w);}
    for(int i=1;i<=m;i++){tq[i].l=read();tq[i].r=read();}
    l--;r++;r++;
    while(l<=r)
    {
        int mid=(l+r)/2;
        if(bl(mid))l=mid+1;
        else r=mid-1;
        ans=min(ans,llabs(s-sum));
    }
    cout<<ans;
}