pascal 100以内奇数求和

var
s,i:integer;
begin
s:=0;
for i:=1 to 100 do
if i mod 2=1 then s:=s+i;
writeln(s);
end.

var
i,ans:integer;
begin
ans:=0;//初始化
for i:=1 to 100 do
if odd(i)//是求奇偶的函数，奇数TRUE，偶数FALSE
inc(ans,i);//统计
writeln(ans);//输出
end.

1+3+5...99=(1+99)*25=2500

var
sum:longint;//总和
i:longint;
begin
for i:=0 to 49 do
inc(sum,i*2+1);
writeln(sum);
end.

var a,i:integer;
begin
a:=0;
for i:=1 to 50 do
a:=a+2*i-1;
writeln(a:6);
end.

var a,i:integer;
begin
a:=0;
for i:=1 to 50 do
a:=a+2*i-1;
writeln(a:6);
end.