※ 引述《woncho ( )》之銘言：
: (1) sum = 10;
: for i = 1 to 10
: for j = 1 to i
: sum = sum + j;
: write sum;
: (2) sum = 0;
: for i = 1 to 10
: for j = i to 10
: sum = sum + j;
: write sum;
: 請教以上兩題的解法，謝謝!!
10 i
Σ Σ j = 220 220 + 10 = 230
i=1 j=1
10 i
Σ (55 -Σ j + i) = 550 -220 + 55 = 385
i=1 j=1
第二題是
10+9+8+7+...+3+2+1 = (10+9+...+2+1) -1 + 1
10+9+8+7+...+3+2 = (10+9+...+2+1) -(1+2) + 2
10+9+8+7+...+3 = (10+9+...+2+1) -(1+2+3) + 3
...
10 = (10+9+...+2+1) -(10+9+...+2+1) + 10
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◆ From: 220.136.244.169
※ 編輯: Lautreamont 來自: 220.136.244.169 (03/10 01:29)