n,*r,=map(int,open(0).read().split());f=[0];*j,=sorted(range(n),key=lambda x:r[x*2]);z=d=0 for _ in j:b=r[_*2+1];f.append(d:=d+b) m=r[(j[0]<<1)] for i in range(n): a=r[j[i]<<1] z=max(z,f[i+1]-a+m) m=max(m,a-f[i]) print(z)

Compiling 'art.py'...

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  adding: __main__.pyc (deflated 31%)

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