#include<iostream> // cin\cout\endl using namespace std; int main(){ //n组数据，每一组数据存入a和b，a\b反转存入rev_a,rev_b中 int n,a,b,rev_a,rev_b; cin>>n;//录入数据的数量 while(n--){ cin>>a>>b;//录入每一组数据的a和b //求rev_a和rev_b int temp; //求rev_a temp=a;//a存入temp中，用于反转存入rev_a rev_a=0;//初始化rev_a为0 while(temp!=0){ rev_a=rev_a*10+temp%10; temp/=10; } //求rev_b temp=b;//b存入temp中，用于反转存入rev_b rev_b=0;//初始化rev_b为0 while(temp!=0){ rev_b=rev_b*10+temp%10; temp/=10; } //求a+b的反转 temp=a+b;//a+b存入temp中，用于反转存入rev_ab int rev_ab=0;//初始化rev_ab为0 while(temp!=0){ rev_ab=rev_ab*10+temp%10; temp/=10; } //判断rev_ab是否==rev_a+rev_b; if(rev_ab==rev_a+rev_b) cout<<rev_ab; else cout<<"NO"; cout<<endl; } return 0; }