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| #include <iostream>
#include <cstdio>
#include <algorithm>
#include <cstring>
#define maxn 1010
#define cn const node
#define INF 1000000000
using namespace std;
int n, m, t;
struct node {
int p, t;
friend bool operator < (cn &u, cn &v) { return u.p < v.p; }
} a[maxn];
int f[maxn][maxn][2];
int main() {
cin >> n >> m >> t;
for (int i = 1; i <= n; ++i) cin >> a[i].p >> a[i].t;
sort(a + 1, a + n +1); memset(f, 10, sizeof f);
f[1][n][0] = max(a[1].p, a[1].t); f[1][n][1] = max(a[n].p, a[n].t);
for (int l = n - 1; l; --l)
for (int i = 1; i + l - 1 <= n; ++i) {
int j = i + l - 1;
f[i][j][0] = min(max(f[i - 1][j][0] + a[i].p - a[i - 1].p, a[i].t),
max(f[i][j + 1][1] + a[j + 1].p - a[i].p, a[i].t));
f[i][j][1] = min(max(f[i - 1][j][0] + a[j].p - a[i - 1].p, a[j].t),
max(f[i][j + 1][1] + a[j + 1].p - a[j].p, a[j].t));
}
int ans = INF;
for (int i = 1; i <= n; ++i) ans = min(ans, f[i][i][0] + abs(a[i].p - t));
cout << ans << endl;
return 0;
}
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