int a = 1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37+38+39+40+41+42+43+44+45+46+47+48+49+50+51+52+53+54+55+56+57+58+59+60+61+62+63+64+65+66+67+68+69+70 +71+72+73+74+75+76+77+78+79+80+81+82+83+84+85+86+87+88+89+90+91+92+93+94+95+96+97+98+99+100; System.out.println(a);
方法2: int a = (1 + 100) * 50; System.out.println(a);方法3: System.out.println("1 加到 100 为:" + 5050);
+71+72+73+74+75+76+77+78+79+80+81+82+83+84+85+86+87+88+89+90+91+92+93+94+95+96+97+98+99+100;
System.out.println(a);
int a = (1 + 100) * 50;
System.out.println(a);方法3:
System.out.println("1 加到 100 为:" + 5050);
int f_sum(int n)
{
return (n + 1) * n / 2;
}int main(int argc, char **argv)
{
fprintf(stdout, "%d\n", f_sum(100));
return 0;
}
static int sum=0;
public static void sum(int count)
{
if(count>0)
{
sum=sum+count;
sum(count-1);
}
}
public static void main(String[] args)
{
sum(100);
System.out.println(sum);
}通过递归实现....
$.ajax({
url: 'www.baidu.com/s?w=一到一百的和',
type: 'GET',
dataType: 'txt/html',
timeout: 1000,
success: function(txt){
alert(txt)
}
});
在构造器里面做一个自加
class A{
public static sum = 0;
public static order = 0;
public A{
sum += ++order ;
}
}
对这个对象new 100次,然后读出sum就可以了。
public int sum(n){
if (n != 0)
return n + sum(n - 1);
}
调用的话:
sum(100);
int sun=100/2*101
public static void main(String[] args) {
int i = 1;
int day = 100;
int sum = 0;
for (int j = 0; j < day; j++) {
sum += i;
i++;
}
System.out.println("1+2+3+..+..100="+sum+);
}}
if (n >= 0) {
if (n == 0)
return n;
else {
return n + sum(n - 1);
}
}
return -1;
}