CodeForces

B. Cover Points
time limit per test1 second
memory limit per test256 megabytes
inputstandard input
outputstandard output
There are n points on the plane, (x1,y1),(x2,y2),…,(xn,yn).

You need to place an isosceles triangle with two sides on the coordinate axis to cover all points (a point is covered if it lies inside the triangle or on the side of the triangle). Calculate the minimum length of the shorter side of the triangle.

Input
First line contains one integer n (1≤n≤105).

Each of the next n lines contains two integers xi and yi (1≤xi,yi≤109).

Output
Print the minimum length of the shorter side of the triangle. It can be proved that it’s always an integer.

Examples
inputCopy
3
1 1
1 2
2 1
outputCopy
3
inputCopy
4
1 1
1 2
2 1
2 2
outputCopy
4
Note
Illustration for the first example:

Illustration for the second example:

题意是找一个三角形把所有点都覆盖，求等腰三角形最短边长。额他的长度因为是等腰直角三角型，很奇怪，最大的X+Y正好是最短边长。

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n,a,b,max2=0;
    cin>>n;
    while(n--)
    {
        scanf("%d %d",&a,&b);
        max2=max(a+b,max2);
    }
    cout<<max2<<endl;
    return 0;
}