Yuki 131 マンハッタン距離 ( Binary Search )
No.131 マンハッタン距離 - yukicoder
よくわかんないけど、とにかく二分探査!
#include <bits/stdc++.h> using namespace std; signed main(){ int x, y, d; cin >> x >> y >> d; x = min( x, d ); y = min( y, d ); if( not ( x >= y ) ) swap( x, y ); int a = -1; int lb = 0, rb = x; while( lb <= rb ){ int mid = lb + rb >> 1; if( mid + y >= d ) a = mid, rb = mid - 1; else lb = mid + 1; } if( a == -1 ) cout << 0 << endl, exit( 0 ); cout << x - a + 1 << endl; return 0; }