基本代码汇总整理.docVIP

《基础代码汇总整理》 WQ @ YCOI 十进制转换K进制 function dectok(x,k:longint):string; const alph=0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ; var st:string; begin st:=; while x0 do begin st:=alph[x mod k+1]+st; x:=x div k; end; exit(st); end; K进制转换十进制 function ktodec(st:string; k:longint):longint; const alph=012456789ABCDEFGHIJKLMNOPQRSTUVWXYZ; var i,j,ans:longint; begin ans:=0; j:=1; for i:=length(st) downto 1 do begin inc(ans,j*(pos(st[i],alph)-1)); j:=j*k; end; exit(ans); end; 欧几里得算法 function gcd(a,b:longint):longint; begin if b=0 then exit(a) else exit(gcd(b,a mod b)); end; 求最小公倍数 function lcm(a,b:longint):longint; begin exit(a div gcd(a,b) *b); end; 判断质数 function judgeprime(x:longint); var i:longint; begin if x=1 then exit(false); for i:=2 to trunc(sqrt(x)) do if x mod i=0 then exit(false); exit(true); end; 生成质数表 procedure makeprime; var i,j:longint; begin fillchar(f,sizeof(f),0); f[1]:=true; for i:=2 to n do if (not f[i]) and (i10000) then begin j:=i*i; while j=n do begin f[j]:=true; inc(j,i); end; end; end; 简单高精度运算系列 procedure change(st:string; var x:array of longint); begin x[0]:=0; while length(st)=4 do begin inc(x[0]); val(copy(st,length(st)-3,4),x[x[0]]); delete(st,length(st)-3,4); end; inc(x[0]); val(st,x[x[0]]); end; function compare(a,b:array of longint):boolean; var i:longint; begin if a[0]b[0] then exit(true); if a[0]b[0] then exit(false); for i:=a[0] downto 1 do if a[i]b[i] then exit(true) else if a[i]b[i] then exit(false); exit(true); end; procedure highplus(a,b:array of longint; var c:array of longint); var i:longint; begin fillchar(c,sizeof(c),0); if a[0]b[0] then c[0]:=a[0] else c[0]:=b[0]; for i:=1 to c[0] do inc(c[i],a[i]+b[i]); for i:=1 to c[0] do if c[i]=10000 then begin dec(c[i],10000); inc(c[i+1]); end; while c[c[0]+1]0 do inc(c[0])