Submission #1293820

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Source Code Expand

#include <cstdio>
#include <algorithm>
#include <string>

#define maxn 5010
#define inf (ll) 1<<30 

using namespace std ;
typedef long long ll ;
int A,B ;
int stack[maxn] ;
int top = 0 ;
string ans ;
char tmp[100] ;

int main(void){
	scanf("%d%d",&A,&B) ;
	if(A<=B) {
		printf("Impossible\n") ;
		return 0 ;
	}
	int total = A + B ;
	stack[top] = 0 ;top ++ ;
	for(int i=1; i<total; i++ ) {
		if(top==0) {
			stack[top] = i ; top ++ ;
		}
		else  {
			printf("? %d %d\n",stack[top-1],i) ;
			char ch ;
			scanf("%*c%c",&ch) ;
			if(ch=='Y') {
				stack[top] = i ; top ++ ;
			} else {
				if(top>0) top-- ;
			}
		}
	}
//	for(int i=0; i<top; i++) printf("%d ",stack[i]) ;
//	printf("hahah\n") ;
	if(top==0) {
		printf("Impossible\n") ;
		return 0 ;	
	}
	ans = "! " ;  //! 101
	int k = stack[top-1] ;
	for(int i=0; i<total; i++) {
		if(i!=k) {
			printf("? %d %d\n",k,i) ;
			char ch ;
			scanf("%*c%c",&ch) ;
			if(ch=='Y') ans += '1' ;
			else ans += '0' ;
			
		} else ans += '1' ;
	}

	printf("%s\n",ans.c_str()) ;


	return 0 ;

}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:17:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&A,&B) ;
                      ^
./Main.cpp:31:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
    scanf("%*c%c",&ch) ;
                       ^
./Main.cpp:51:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
    scanf("%*c%c",&ch) ;
                       ^

Judge Result