#include<stdio.h>#include<string.h>#include<algorithm>using namespace std;struct dian{ int s; int e; int l;}d[100015],d1[100015];bool cmp(struct dian a,struct dian b){ if(a.s==b.s) return a.e<b.e; return a.s<b.s;}int main(){ int t,i,j; int st,en; int m,flag; int max1; int x,y; int sum,flag1; int k; while(scanf("%d",&m)!=EOF) { flag=0; sum=0; k=0; while(1) { scanf("%d%d",&x,&y); if(x==0&&y==0) break; d[k].s=x; d[k].e=y; d[k].l=y-x; k++; } sort(d,d+k,cmp); st=0; int kk=0; int pos=100005; int jl=0; while(st<m&&flag==0) { max1=-100005; pos=100005; for(i=kk;i<k;i++) { if(d[i].s<=st&&d[i].e>=st) { if(d[i].e>max1) max1=d[i].e,pos=i; kk++; } else if(d[i].s>st) break; } if(pos==100005) { flag=1; break; } st=max1; sum++; d1[jl].s=d[pos].s; d1[jl++].e=d[pos].e; } if(flag==0) { printf("%dn",sum); for(i=0;i<jl;i++) { printf("%d %dn",d1[i].s,d1[i].e); } } if(flag==1) printf("No solutionn"); }}
