[c++] 교집합, 연속된 자연수

• 교집합

timelimit 난 코드
#include <iostream>

/* run this program using the console pauser or add your own getch, system("pause") or input loop */
using namespace std;
int main() {
	//freopen("input.txt", "rt", stdin);
	int n, m, i, j, k, l, tmp, p1, p2, p3;
	int a[101], b[101], c[201];
	scanf("%d", &n);
	for(i=1; i<=n; i++){
		scanf("%d", &a[i]);
	}
	
	scanf("%d", &m);
	for(i=1; i<=m; i++){
		scanf("%d", &b[i]);
	}

	for(i=2; i<=n; i++){
		tmp=a[i];
		for(j=i-1; j>0; j--){
			if(tmp<a[j]) {
				a[j+1]=a[j];
			}else {
				break;
			}
		}
		a[j+1]=tmp;
	}
	
	for(i=2; i<=m; i++){
		tmp = b[i];
		for(j=i-1; j>0; j--){
			if(tmp<b[j]) {
				b[j+1]=b[j];
			}else {
				break;
			}
		}
		b[j+1]=tmp;
	}
	p1=1;
	p2=1;
	p3=1;
	while(p1<=n && p2<=m){
		if(a[p1]==b[p2]){
			c[p3]=a[p1];
			p1++;
			p2++;
			p3++;
		}
		else if(a[p1]>b[p2]){
			p2++;
		}
		else if(a[p1]<b[p2]){
			p1++;	
		}
	}

	for(i=1; i<p3; i++){
		printf("%d ", c[i]);
	}
	
	return 0;
}


sort 사용
#include <iostream>
#include <vector>
#include <algorithm>

/* run this program using the console pauser or add your own getch, system("pause") or input loop */
using namespace std;
int main() {
	//freopen("input.txt", "rt", stdin);
	int n, m, i, j, k, l, tmp, p1, p2, p3;
	
	scanf("%d", &n);
	vector<int> a(n);
	for(i=0; i<n; i++){
		scanf("%d", &a[i]);
	}
	
	scanf("%d", &m);
	vector<int> b(m), c(n+m);
	for(i=0; i<m; i++){
		scanf("%d", &b[i]);
	}
	sort(a.begin(), a.end());	
	sort(b.begin(), b.end());	
	
	p1=0;
	p2=0;
	p3=0;
	while(p1<n && p2<m){
		if(a[p1]==b[p2]){
			c[p3]=a[p1];
			p1++;
			p2++;
			p3++;
		}
		else if(a[p1]>b[p2]){
			p2++;
		}
		else if(a[p1]<b[p2]){
			p1++;	
		}
	}

	for(i=0; i<p3; i++){
		printf("%d ", c[i]);
	}
	
	return 0;
}

 

• 연속된 자연수

#include <iostream>
#include <vector>
#include <algorithm>

/* run this program using the console pauser or add your own getch, system("pause") or input loop */
using namespace std;
int main() {
	//freopen("input.txt", "rt", stdin);
	int n, m, i, j, k, l, cnt=0,sum, p1, p2, p3;
	
	scanf("%d", &n);
	for(i=n; i>0; i--){
		sum = 0;
		p1=0;
		for(j=i; j<n; j++){
			sum += j;
			p1++;
			if(sum==n) {
				cnt++;
				//printf("%d + ", i);
				for(k=0; k<p1; k++){
					if(k<p1-1){
						printf("%d + ", i+k);						
					}
					else if(k==p1-1){
						printf("%d = ", i+k);
					}					

				}
				printf("%d\n", n);
				break;	
			}
		}
	
	}
	printf("%d", cnt);
	
	return 0;
}


#include <iostream>
#include <vector>
#include <algorithm>

/* run this program using the console pauser or add your own getch, system("pause") or input loop */
using namespace std;
int main() {
	//freopen("input.txt", "rt", stdin);
	int n, m, i, j, k, l, cnt=0, sum, tmp, rst, shr;
	int a[1001];
	scanf("%d", &n);
	for(i=2; i<=n; i++){
		sum=0;
		for(j=1; j<=i; j++){
			sum+=j;
		}

		tmp=n-sum;
		if(tmp<0) break;
		rst=tmp%i;
		if(rst==0){
			shr=tmp/i;
			cnt++;
			for(k=1; k<=i; k++){
				if(k<i){
					printf("%d + ", shr+k);						
				}
				else if(k==i){
					printf("%d = ", shr+k);
				}
					
			}
			printf("%d\n", n);
		}			
	}
	printf("%d", cnt);
	return 0;
}