PAT甲级1065. A+B and C (64bit) (20)

Given three integers A, B and C in [-263, 263], you are supposed to tell whether A+B > C.
Input Specification:
The first line of the input gives the positive number of test cases, T (<=10). Then T test cases follow, each consists of a single line containing three integers A, B and C, separated by single spaces.
Output Specification:
For each test case, output in one line “Case #X: true” if A+B>C, or “Case #X: false” otherwise, where X is the case number (starting from 1).
Sample Input:
3
1 2 3
2 3 4
9223372036854775807 -9223372036854775808 0
Sample Output:
Case #1: false
Case #2: true
Case #3: false

只有正数加正数或负数加负数（即同号相加时才会溢出）。其他情况，直接加就好了。

#include <iostream>using namespace std; int main(){  int T;  cin>>T;  long long int A,B,C,S;  for(int i=1;i<=T;i++){    cin>>A>>B>>C;    S=A+B;    if(A>0&&B>0&&S<=0) cout<<"Case #"<<i<<": true"<<endl;    else if(A<0&&B<0&&S>=0) cout<<"Case #"<<i<<": false"<<endl;    else if(S>C) cout<<"Case #"<<i<<": true"<<endl;    else cout<<"Case #"<<i<<": false"<<endl;  }  return 0;}