for循环的基础计算

//1.计算0到100之间的奇数和偶数的和(快捷键 100.for即可打出循环体)
int oddNum = 0;
int evenNum = 0;
for (int i = 0; i < 100; i++) {
//%是取模运算
if (i % 2 != 0) {
oddNum += i;
} else {
evenNum += i;
}
}
System.out.println("oddNum：" + oddNum);
System.out.println("evenNum：" + evenNum);

//2.用for循环打印出1-1000之间可以被5整除的数，并且每行输出三个

for (int i = 0; i < 1000; i++) {
if (i % 5 == 0 && i != 0) {
System.out.print(i + "\t");
}
if (i % (5 * 3) == 0) {
System.out.println();
}
}
System.out.println();

//3.用for循环打印99乘法表
for (int i = 1; i < 10; i++) {
for (int k = 1; k <= i; k++) {
System.out.print(k+"*"+i+"="+(i*k)+"\t");
}
System.out.println();
}

//4.质数， 只能被1和它本身整除的数字叫质数

//5.打印金字塔三角形
for (int i = 0; i < 5; i++) {
for (int j = 5; j > i; j--) {
System.out.print(" ");
}
for (int j = 0; j <= i; j++) {
System.out.print("#");
}
for (int j = 0; j < i; j++) {
System.out.print("%");
}
System.out.println("");
}