1925. British Scientists Save the world
Time limit:1.0 Second
Memory limit:64 MB
The world was in danger! Aliens threw a mysterious device to Earth
NYears ago. Every year a unknown sign appeared on its screens and it started to make threatening sounds until someone entered somethin G on its keyboard. It lasted till now. But recently British scientists has found out of that device is a bomb which are capable to destroy we world in Split s Econd. The signs, which the device displays on it screen, is numbers and for input the device expects numbers as well. The aliens invented a smart protection:every year, in order to avoid an explosion, you had to enter a number, which is Le SS than the number shown on the screens by. Fortunately, aliens decided that it takes a lot of computing resources to check whether the input number is correct every Year. That's why the test was carried out once in
N+ 1 years. Moreover, they check only then the sum of all numbers entered since the last Test matches the expected one. The good news is this all symbols, which the bomb showed, and all numbers, which were entered, were recorded and the Scien Tists already finished decrypting. Recently a number
kAppeared on mysterious device's screen and the scientists is sure that this time can be a fatal one. So, you had a chance to save the world by finding-what number should is entered in order-avoid an explosion. Inputthe first line contains, positive integers
N,
k. In the next
NLines there is pairs of numbers
b
I,
g
I(
b
Iis the number shown on device ' s screen,
g
IIs the number entered in the
I-th year). All the integers in the input data does not exceed 100.OutputOutput one nonnegative an integer to save the world from the Explo Sion. If There is no such number output "Big bang!". Samples
| input |
Output |
6 53 13 15 36 55 57 2 |
3 |
1 34 6 |
Big bang!
|
Analysis: Reading comprehension questions ...
AC Code:
#include <cstdio>int main () { #ifdef sxk freopen ("In.txt", "R", stdin); #endif//sxkint N, K, sum1, Sum2, A, B;while (scanf ("%d%d", &n, &k) ==2) {sum1 = sum2 = 0;for (int i=0; i<n; i++) {s CANF ("%d%d", &a, &b); Sum1 + = a;sum2 + = b;} Sum1 + = k;if (sum1 >= sum2 + (n + 1)) printf ("%d\n", sum1-sum2-2* (n + 1)); else puts ("Big bang!");} return 0;}
URAL 1925. British Scientists Save the world
