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https://github.com/Kiritow/OJ-Problems-Source.git
synced 2024-03-22 13:11:29 +08:00
37 lines
1008 B
C++
37 lines
1008 B
C++
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#include <stdio.h>
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#include <string.h>
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#include <algorithm>
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using namespace std;
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const int M=2005;
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#define min(a,b) a<b?a:b
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int map[M][M];
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#define inf 0xffffff
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int main()
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{
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int n,m,i,j,k,s,e,l,s1,e1;
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while(scanf("%d%d",&n,&m)!=EOF)
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{
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for(i=0;i<n;i++)
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for(j=0;j<n;j++)
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map[i][j]=inf;
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for(i=0;i<m;i++)
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{
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scanf("%d%d%d",&s,&e,&l);
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if(map[s][e]>l)
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map[s][e]=map[e][s]=l;
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}
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for(k=0;k<n;k++)
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for(i=0;i<n;i++)
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for(j=0;j<n;j++)
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map[i][j]=min(map[i][j],map[i][k]+map[k][j]);
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scanf("%d%d",&s1,&e1);
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if(s1==e1)
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printf("0\n");
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else if(map[s1][e1]==inf)
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printf("-1\n");
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else
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printf("%d\n",map[s1][e1]);
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}
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return 0;
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}
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