标签：style blog color os io ar for div log
这个按自己的思路，超时，网上找到的资料，这个最简单，可是有2句至今还不明白其义：
/* ID: qq104801 LANG: C++ TASK: pprime */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <assert.h> #include <math.h> char x[11]; int a,b; int isprime(int n) { if (n%2==0)return 0; for(int i=3;i*i<=n;i+=2) if(n%i==0)return 0; return 1; } int modify(int x) { int t=x;x/=10; while(x>0){ t=t*10+x%10; x/=10; } return t; } void test() { FILE *fin = fopen("pprime.in", "r"); FILE *fout = fopen("pprime.out", "w"); fscanf(fin,"%d %d",&a,&b); if(a<=5&&5<=b)fprintf(fout,"5\n"); if(a<=7&&7<=b)fprintf(fout,"7\n"); if(a<=11&&11<=b)fprintf(fout,"11\n"); int i=10,j,k; while(modify(i)<a)i++; while(modify(i)<=b) { k=i;j=1; while(k>9){k/=10;j*=10;} if(k%2==0){i+=j;continue;} j=modify(i); if(isprime(j)) fprintf(fout,"%d\n",j); i++; } fclose(fin); fclose(fout); } main () { //printf("%d\n",ispalindromes(11)); test(); //printf("%d\n",modify(32)); exit (0); }
测试结果：
USER: cn tom [qq104801] TASK: pprime LANG: C++ Compiling... Compile: OK Executing... Test 1: TEST OK [0.005 secs, 3496 KB] Test 2: TEST OK [0.003 secs, 3496 KB] Test 3: TEST OK [0.008 secs, 3496 KB] Test 4: TEST OK [0.011 secs, 3496 KB] Test 5: TEST OK [0.011 secs, 3496 KB] Test 6: TEST OK [0.008 secs, 3496 KB] Test 7: TEST OK [0.024 secs, 3496 KB] Test 8: TEST OK [0.022 secs, 3496 KB] Test 9: TEST OK [0.030 secs, 3496 KB] All tests OK. Your program (‘pprime‘) produced all correct answers! This is your submission #3 for this problem. Congratulations! Here are the test data inputs: ------- test 1 ---- 5 500 ------- test 2 ---- 750 14000 ------- test 3 ---- 123456 1123456 ------- test 4 ---- 97000 1299000 ------- test 5 ---- 9878210 9978210 ------- test 6 ---- 9902099 9902100 ------- test 7 ---- 7 10000000 ------- test 8 ---- 1333331 9743479 ------- test 9 ---- 5 100000000 Keep up the good work! Thanks for your submission!
标签：style blog color os io ar for div log
原文地址：http://www.cnblogs.com/dpblue/p/3950595.html
