题目地址

Given three integers A, B and C in [−2
​63
​​ ,2
​63
​​ ], 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

#include<stdio.h>
int main(){
    long long a,b,c,res;int n;bool flag;
//    for()
    scanf("%d",&n);
    // if(n<=10)
    for(int i=1;i<=n;i++){
        scanf("%lld%lld%lld",&a,&b,&c);
        res=a+b;
        if(a>0&&b>0&&res<=0) flag=true; //正溢出正确，负溢出错误，注意必须先算res，res要带小于号；
        else if(a<0&&b<0&&res>=0) flag=false;
        else if(res>c) flag=true;
        else flag=false;
        if(flag==true)
        printf("Case #%d: true\n",i);
        else printf("Case #%d: false\n",i);
    }
    return 0;
}